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Scientific reproducibility and Open Science may seem like a "new" approach to Science, but these concepts are in fact fundamental principles of the Scientific Method, established a thousand years ago. By definition, scientists want to follow the Scientific Method. Then why have different studies demonstrated that researchers have difficulties reproducing even their own methods? Clues can be found in a system where science is being drowned by numerical ranking, favouring productivity over discovery. Given the current epoch of economic crisis, where researchers are forced into a competitive game of pandering to panelists in quests for funds, it seems to be a good time for deep reflection on the entire scientific system, and on how to support good ideas versus good marketing. The challenge will be harder when facilities like the Square Kilometre Array Observatory start generating data volumes reaching the exa-scale. Not only will computing, networking or storage resources reach their limits, but the biggest challenge will be scientific: Extracting knowledge will become an impossible task without a fundamental change in methodology and policies in the short-term. Computing facilities enabling science in Big Data oriented facilities should be key in supporting astronomers to build reproducible methods. I will discuss how different research communities (such as individual researchers, large collaborations, data centres, journals and their referees) as well as policy makers, view the challenges/barriers and rewards of reproducibility. For scientific facilities, adoption of Open Science is both a need and a duty. Open Science not only enhances scientific collaboration and knowledge interchange in a transparent way. It also brings a wider impact in other areas, by encouraging the democratisation of science, contributing to achieving UN's Sustainable Development Goals. With this talk I aim to provoke extra critical thinking among the different actors involved in our system (applicants for jobs/grants, referees, or ...

Full list of authors: Wong, O.; Stevens, A. R. H.; For, B. -Q.; Westmeier, T.; Dixon, M.; Oh, S. -H.; Józsa, G. I. G.; Reynolds, T. N.; Lee-Waddell, K.; Román, J.; Verdes-Montenegro, L.; Courtois, H. M.; Pomarède, D.; Murugeshan, C.; Whiting, M.; Bekki, K.; Bigiel, F.; Bosma, A.; Catinella, B.; Dénes, H.; Elagali, A.; Holwerda, B. W.; Kamphuis, P.; Kilborn, V. A.; Kleiner, D.; Koribalski, B. S.; Lelli, F.; Madrid, J. P.; McQuinn, K. B. W.; Popping, A.; Rhee, J.; Roychowdhury, S.; Scott, T. C.; Sengupta, C.; Spekkens, K.; Staveley-Smith, L.; Wakker, B. P. ; We present the Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pre-pilot observations of two 'dark' H i sources (with H i masses of a few times 108 {M}_\odot and no known stellar counterpart) that reside within 363 kpc of NGC 1395, the most massive early-type galaxy in the Eridanus group of galaxies. We investigate whether these 'dark' H i sources have resulted from past tidal interactions or whether they are an extreme class of low surface brightness galaxies. Our results suggest that both scenarios are possible, and not mutually exclusive. The two 'dark' H i sources are compact, reside in relative isolation, and are more than 159 kpc away from their nearest H i-rich galaxy neighbour. Regardless of origin, the H i sizes and masses of both 'dark' H i sources are consistent with the H i size-mass relationship that is found in nearby low-mass galaxies, supporting the possibility that these H i sources are an extreme class of low surface brightness galaxies. We identified three analogues of candidate primordial 'dark' H i galaxies within the TNG100 cosmological, hydrodynamic simulation. All three model analogues are dark matter dominated, have assembled most of their mass 12-13 Gyr ago, and have not experienced much evolution until cluster infall 1-2 Gyr ago. Our WALLABY pre-pilot science results suggest that the upcoming large-area H i surveys will have a significant impact on our understanding of low surface brightness galaxies and the physical processes that shape them. © 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. ; Parts of this research was supported by the Australian Research Council Centre of Excellence for All-sky Astrophysics in 3 Dimensions (ASTRO 3D) through project number CE170100013. SHO acknowledges support from the National Research Foundation of Korea (NRF) grant funded by the Korea government (Ministry of Science and ICT: MSIT) (No. NRF-2020R1A2C1008706). LVM and JR acknowledges financial support from the grants AYA2015-65973-C3-1-R and RTI2018-096228-B-C31 (MINECO/FEDER, UE), as well as from the State Agency for Research of the Spanish MCIU through the 'Center of Excellence Severo Ochoa' award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). JR acknowledges support from the State Research Agency (AEI-MCINN) of the Spanish Ministry of Science and Innovation under the grant 'The structure and evolution of galaxies and their central regions' with reference PID2019-105602GB-I00/10.13039/501100011033. FB acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 - Research and Innovation Framework Programme (grant agreement No.726384/Empire). AB acknowledges support from the Centre National d'Etudes Spatiales (CNES), France. PK is partially supported by the BMBF project 05A17PC2 for D-MeerKAT. This work was supported by Fundação para a Ciência e a Tecnologia (FCT) through the research grants UIDB/04434/2020 and UIDP/04434/2020. TCS acknowledges support from FCT through national funds in the form of a work contract with the reference DL 57/2016/CP1364/CT0009. The Australian SKA Pathfinder is part of the Australia Telescope National Facility which is managed by CSIRO. Operation of ASKAP is funded by the Australian Government with support from the National Collaborative Research Infrastructure Strategy. ASKAP uses the resources of the Pawsey Supercomputing Centre. Establishment of ASKAP, the Murchison Radio-astronomy Observatory, and the Pawsey Supercomputing Centre are initiatives of the Australian Government, with support from the Government of Western Australia and the Science and Industry Endowment Fund. ; Peer reviewed

Full list of authors: de Blok, W. J. G.; Athanassoula, E.; Bosma, A.; Combes, F.; English, J.; Heald, G. H.; Kamphuis, P.; Koribalski, B. S.; Meurer, G. R.; Román, J.; Sardone, A.; Verdes-Montenegro, L.; Bigiel, F.; Brinks, E.; Chemin, L.; Fraternali, F.; Jarrett, T.; Kleiner, D.; Maccagni, F. M.; Pisano, D. J.; Serra, P.; Spekkens, K.; Amram, P.; Carignan, C.; Dettmar, R. -J.; Gibson, B. K.; Holwerda, B. W.; Józsa, G. I. G.; Lucero, D. M.; Oosterloo, T. A.; Ramaila, A. J. T.; Ramatsoku, M.; Sheth, K.; Walter, F.; Wong, O. I.; Zijlstra, A. A.; Bloemen, S.; Groot, P. J.; Le Poole, R.; Klein-Wolt, M.; Körding, E. G.; McBride, V. A.; Paterson, K.; Pieterse, D. L. A.; Vreeswijk, P.; Woudt, P. A. ; Aims. We present the results of three commissioning H I observations obtained with the MeerKAT radio telescope. These observations make up part of the preparation for the forthcoming MHONGOOSE nearby galaxy survey, which is a MeerKAT large survey project that will study the accretion of gas in galaxies and the link between gas and star formation. Methods. We used the available H I data sets, along with ancillary data at other wavelengths, to study the morphology of the MHONGOOSE sample galaxy, ESO 302-G014, which is a nearby gas-rich dwarf galaxy. Results. We find that ESO 302-G014 has a lopsided, asymmetric outer disc with a low column density. In addition, we find a tail or filament of H I clouds extending away from the galaxy, as well as an isolated H I cloud some 20 kpc to the south of the galaxy. We suggest that these features indicate a minor interaction with a low-mass galaxy. Optical imaging shows a possible dwarf galaxy near the tail, but based on the current data, we cannot confirm any association with ESO 302-G014. Nonetheless, an interaction scenario with some kind of low-mass companion is still supported by the presence of a significant amount of molecular gas, which is almost equal to the stellar mass, and a number of prominent stellar clusters, which suggest recently triggered star formation. Conclusions. These data show that MeerKAT produces exquisite imaging data. The forthcoming full-depth survey observations of ESO 302-G014 and other sample galaxies will, therefore, offer insights into the fate of neutral gas as it moves from the intergalactic medium onto galaxies. © ESO 2020. ; It is a pleasure to thank the MeerKAT commissioning team without whom this paper would not have been possible. The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation. (Part of) the data published here have been reduced using the CARACal pipeline, partially supported by ERC Starting grant number 679627 "FORNAX", MAECI Grant Number ZA18GR02, DST-NRF Grant Number 113121 as part of the ISARP Joint Research Scheme, and BMBF project 05A17PC2 for D-MeerKAT. Information about CARACal can be obtained online under the URL: https://caracal.readthedocs.io.This work is partly based on data obtained with the MeerLICHT telescope, located at the SAAO Sutherland station, South Africa. The MeerLICHT telescope is run by the MeerLICHT consortium, on behalf of Radboud University, the University of Cape Town, the Netherlands Foundation for Scientific Research (NWO), the National Research Facility of South Africa through the South African Astronomical Observatory, the University of Oxford, the University of Manchester and the University of Amsterdam. The work of PK is partially supported by the BMBF project 05A17PC2 for D-MeerKAT. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement no. 679627; project name FORNAX). BKG acknowledges the UK's Science & Technology Facilities Council (STFC), through the University of Hull Consolidated Grant (ST/R000840/1). KS acknowledges funding from the Natural Sciences and Engineering Council of Canada (NSERC). AS is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-1903834. EA and AB thank the CNES for financial support. The work of DJP was partially supported by NSF CAREER grant AST-1149491. FB acknowledges funding from the European Union's Horizon 2020 research and innovation programme (grant agreement no. 726384/EMPIRE). LVM and JR acknowledge financial support from the grants AYA2015-65973-C3-1-R and RTI2018-096228-B-C31 (MINECO/FEDER, UE), as well as from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709). ; Peer reviewed

We estimate the H i mass function (HIMF) of galaxies in groups based on thousands of ALFALFA (Arecibo Legacy Fast ALFA survey) H i detections within the galaxy groups of four widely used SDSS (Sloan Digital Sky Survey) group catalogues. Although differences between the catalogues mean that there is no one definitive group galaxy HIMF, in general we find that the low-mass slope is flat, in agreement with studies based on small samples of individual groups, and that the 'knee' mass is slightly higher than that of the global HIMF of the full ALFALFA sample. We find that the observed fraction of ALFALFA galaxies in groups is approximately 22 per cent. These group galaxies were removed from the full ALFALFA source catalogue to calculate the field HIMF using the remaining galaxies. Comparison between the field and group HIMFs reveals that group galaxies make only a small contribution to the global HIMF as most ALFALFA galaxies are in the field, but beyond the HIMF 'knee' group galaxies dominate. Finally, we attempt to separate the group galaxy HIMF into bins of group halo mass, but find that too few low-mass galaxies are detected in the most massive groups to tightly constrain the slope, owing to the rarity of such groups in the nearby Universe where low-mass galaxies are detectable with existing H i surveys.© 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society ; We acknowledge the work of the entire ALFALFA team for observing, flagging, and performing signal extraction. We thank the anonymous referee for their suggestions that helped to improve this paper. MGJ is supported by a Juan de la Cierva formacion´ fellowship (FJCI-2016-29685) from the Spanish Ministerio de Ciencia, Innovacion y Universidades (MCIU). MGJ and LVM ´ also acknowledge support from the grants AYA2015-65973-C3-1- R (MINECO/FEDER, UE) and RTI2018-096228-B-C31 (MCIU). The research of KMH is supported by the under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement nr. 291531. EAKA is supported by the WISE research programme, which is financed by the Netherlands Organisation for Scientific Research (NWO). This work has been supported by the State Agency for Research of the Spanish MCIU through the 'Centro de Excelencia Severo Ochoa' award to the Instituto de Astrof´ısica de Andaluc´ıa (SEV-2017-0709). This research was supported by the Munich Institute for Astro- and Particle Physics (MIAPP) which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) ; Peer reviewed

Full list of authors: Namumba, B.; Koribalski, B. S.; Józsa, G. I. G.; Lee-Waddell, K.; Jones, M. G.; Carignan, C.; Verdes-Montenegro, L.; Ianjamasimanana, R.; de Blok, W. J. G.; Cluver, M.; Garrido, J.; Sánchez-Expósito, S.; Ramaila, A. J. T.; Thorat, K.; Andati, L. A. L.; Hugo, B. V.; Kleiner, D.; Kamphuis, P.; Serra, P.; Smirnov, O. M.; Maccagni, F. M.; Makhathini, S.; Molnár, D. Cs.; Perkins, S.; Ramatsoku, M.; White, S. V.; Loi, F. ; We report the discovery of large amounts of previously undetected cold neutral atomic hydrogen (H I) around the core triplet galaxies in the nearby NGC 7232 galaxy group with MeerKAT. With a physical resolution of ∼1 kpc, we detect a complex web of low-surface-brightness H I emission down to a 4σ column density level of ∼1 × 1019 cm−2 (over 44 km s−1). The newly discovered H I streams extend over ∼20 arcmin corresponding to 140 kpc in projection. This is approximately three times the H I extent of the galaxy triplet (52 kpc). The H I debris has an H I mass of ∼6.6 × 109 M⊙, more than 50 per cent of the total H I mass of the triplet. Within the galaxy triplet, NGC 7233 and NGC 7232 have lost a significant amount of H I while NGC 7232B appears to have an excess of H I. The H I deficiency in NGC 7232 and NGC 7233 indicates that galaxy–galaxy interaction in the group concentrates on this galaxy pair while the other disc galaxies have visited them over time. In comparison to the AMIGA sample of isolated galaxies, we find that with regards to its total H I mass the NGC 7232/3 galaxy triplet is not H I-deficient. Despite the many interactions associated to the triplet galaxies, no H I seems to have been lost from the group (yet). © 2021 The Author(s). ; The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation. BN's research is supported by the South African Radio Astronomy Observatory (SARAO). We acknowledge the Inter-University Institute for Data Intensive Astronomy (IDIA) for supporting us with the data intensive cloud for data processing. IDIA is a South African university partnership involving the University of Cape Town, the University of Pretoria, and the University of the Western Cape. BN acknowledges financial support from the CSIC Program of Scientific Cooperation for Development i-COOP+2019. The research of OS is supported by the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation. PK is partially supported by the BMBF project 05A17PC2 for D-MeerKAT. LVM, MGJ, and BN acknowledge financial support from the State Agency for Research of the Spanish MCIU through the 'Center of Excellence Severo Ochoa' award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). BN acknowledges the discussion with the AMIGA team at IAA regarding data reduction and analysis. LVM, MJ, SSE, and JG acknowledge as well support from the grants AYA2015-65973-C3-1-R (MINECO/FEDER, UE) and RTI2018-096228-B-C31 (MCIU/AEI/FEDER,UE). MGJ fellowship was supported by a Juan de la Cierva formación fellowship. The work of WJGdB has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 882793/MeerGas). This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement no. 679627; project name FORNAX). MEC is a recipient of an Australian Research Council Future Fellowship (project No. FT170100273) funded by the Australian Government. ; Peer reviewed

Contributions to the XIV.0 Scientific Meeting (virtual) of the Spanish Astronomical Society, held 13-15 July 2020, online at https://www.sea-astronomia.es/reunion-cientifica-2020, id.241. ; With funding from the Spanish government through the 'Severo Ochoa Centre of Excellence' accreditation SEV-2017-0709.

New scientific instruments are starting to generate an unprecedented amount of data. The Low Frequency Array (LOFAR), one of the Square Kilometre Array (SKA) pathfinders, is already producing data on a petabyte scale. The calibration of these data presents a huge challenge for final users: (a) extensive storage and computing resources are required; (b) the installation and maintenance of the software required for the processing is not trivial; and (c) the requirements of calibration pipelines, which are experimental and under development, are quickly evolving. After encountering some limitations in classical infrastructures like dedicated clusters, we investigated the viability of cloud infrastructures as a solution. We found that the installation and operation of LOFAR data calibration pipelines is not only possible, but can also be efficient in cloud infrastructures. The main advantages were: (1) the ease of software installation and maintenance, and the availability of standard APIs and tools, widely used in the industry; this reduces the requirement for significant manual intervention, which can have a highly negative impact in some infrastructures; (2) the flexibility to adapt the infrastructure to the needs of the problem, especially as those demands change over time; (3) the on-demand consumption of (shared) resources. We found that a critical factor (also in other infrastructures) is the availability of scratch storage areas of an appropriate size. We found no significant impediments associated with the speed of data transfer, the use of virtualization, the use of external block storage, or the memory available (provided a minimum threshold is reached). Finally, we considered the cost-effectiveness of a commercial cloud like Amazon Web Services. While a cloud solution is more expensive than the operation of a large, fully-utilized cluster completely dedicated to LOFAR data reduction, we found that its costs are competitive if the number of datasets to be analysed is not high, or if the costs of maintaining a system capable of calibrating LOFAR data become high. Coupled with the advantages discussed above, this suggests that a cloud infrastructure may be favourable for many users. ; We acknowledge the useful comments of the anonymous referee. We would like to acknowledge the work of all the developers and packagers of the LOFAR software that constitute the core of the processing pipelines (including factor, prefactor, LSMTool, LoSoTo, and the Kern Suite), as well as the useful discussions with the participants in the LOFAR blank fields and direction dependent calibration teleconferences over the years. JS and PNB are grateful for financial support from STFC via grant ST/M001229/1. This work has been also supported by the projects 'AMIGA5: gas in and around galaxies. Scientific and technological preparation for the SKA' (AYA2014-52013-C2-1-R) and 'AMIGA6: gas in and around galaxies. Preparation for SKA science and contribution to the design of the SKA data flow' (AYA2015-65973-C3-1-R) both of which were co-funded by MICINN and FEDER funds and the Junta de Andalucía (Spain) grants P08-FQM-4205 and TIC-114. We would like to explicitly acknowledge Dr Jose Ruedas – chief of the computer centre and responsible of the computing and communications infrastructures at IAA-CSIC – and Rafael Parra – system administrator of the IAA computing cluster – for their technical assistance. We acknowledge the joint SKA and AWS Astrocompute proposal call that was used to fund all the tests in the AWS infrastructure with the projects "Calibration of LOFAR ELAIS-N1 data in the Amazon cloud" and "Amazon Cloud Processing of LOFAR Tier-1 surveys: Opening up a new window on the Universe". This work made use of the University of Hertfordshire's high-performance computing facility and the LOFAR-UK computing facility, supported by STFC [grant number ST/P000096/1]. This work benefited from services and resources provided by the fedcloud.egi.eu Virtual Organization, supported by the national resource providers of the EGI Federation. We acknowledge the resources and support provided by the STFC RAL Cloud infrastructure. LOFAR, the Low Frequency Array designed and constructed by ASTRON, has facilities in several countries, that are owned by various parties (each with their own funding sources), and that are collectively operated by the International LOFAR Telescope (ILT) foundation under a joint scientific policy. ; Peer Reviewed ; Award-winning ; Postprint (author's final draft)

New scientific instruments are starting to generate an unprecedented amount of data. The Low Frequency Array (LOFAR), one of the Square Kilometre Array (SKA) pathfinders, is already producing data on a petabyte scale. The calibration of these data presents a huge challenge for final users: (a) extensive storage and computing resources are required; (b) the installation and maintenance of the software required for the processing is not trivial; and (c) the requirements of calibration pipelines, which are experimental and under development, are quickly evolving. After encountering some limitations in classical infrastructures like dedicated clusters, we investigated the viability of cloud infrastructures as a solution. We found that the installation and operation of LOFAR data calibration pipelines is not only possible, but can also be efficient in cloud infrastructures. The main advantages were: (1) the ease of software installation and maintenance, and the availability of standard APIs and tools, widely used in the industry; this reduces the requirement for significant manual intervention, which can have a highly negative impact in some infrastructures; (2) the flexibility to adapt the infrastructure to the needs of the problem, especially as those demands change over time; (3) the on-demand consumption of (shared) resources. We found that a critical factor (also in other infrastructures) is the availability of scratch storage areas of an appropriate size. We found no significant impediments associated with the speed of data transfer, the use of virtualization, the use of external block storage, or the memory available (provided a minimum threshold is reached). Finally, we considered the cost-effectiveness of a commercial cloud like Amazon Web Services. While a cloud solution is more expensive than the operation of a large, fully-utilized cluster completely dedicated to LOFAR data reduction, we found that its costs are competitive if the number of datasets to be analysed is not high, or if the costs of maintaining a system capable of calibrating LOFAR data become high. Coupled with the advantages discussed above, this suggests that a cloud infrastructure may be favourable for many users. ; We acknowledge the useful comments of the anonymous referee. We would like to acknowledge the work of all the developers and packagers of the LOFAR software that constitute the core of the processing pipelines (including factor, prefactor, LSMTool, LoSoTo, and the Kern Suite), as well as the useful discussions with the participants in the LOFAR blank fields and direction dependent calibration teleconferences over the years. JS and PNB are grateful for financial support from STFC via grant ST/M001229/1. This work has been also supported by the projects 'AMIGA5: gas in and around galaxies. Scientific and technological preparation for the SKA' (AYA2014-52013-C2-1-R) and 'AMIGA6: gas in and around galaxies. Preparation for SKA science and contribution to the design of the SKA data flow' (AYA2015-65973-C3-1-R) both of which were co-funded by MICINN and FEDER funds and the Junta de Andalucía (Spain) grants P08-FQM-4205 and TIC-114. We would like to explicitly acknowledge Dr Jose Ruedas – chief of the computer centre and responsible of the computing and communications infrastructures at IAA-CSIC – and Rafael Parra – system administrator of the IAA computing cluster – for their technical assistance. We acknowledge the joint SKA and AWS Astrocompute proposal call that was used to fund all the tests in the AWS infrastructure with the projects "Calibration of LOFAR ELAIS-N1 data in the Amazon cloud" and "Amazon Cloud Processing of LOFAR Tier-1 surveys: Opening up a new window on the Universe". This work made use of the University of Hertfordshire's high-performance computing facility and the LOFAR-UK computing facility, supported by STFC [grant number ST/P000096/1]. This work benefited from services and resources provided by the fedcloud.egi.eu Virtual Organization, supported by the national resource providers of the EGI Federation. We acknowledge the resources and support provided by the STFC RAL Cloud infrastructure. LOFAR, the Low Frequency Array designed and constructed by ASTRON, has facilities in several countries, that are owned by various parties (each with their own funding sources), and that are collectively operated by the International LOFAR Telescope (ILT) foundation under a joint scientific policy. ; Peer Reviewed ; Award-winning ; Postprint (author's final draft)

Using mid-infrared star formation rate and stellar mass indicators in WISE (Wide-field Infrared Survey Explorer), we construct and contrast the relation between star formation rate and stellar mass for isolated and paired galaxies. Our samples comprise a selection of AMIGA (Analysis of the interstellar Medium in Isolated GAlaxies; isolated galaxies) and pairs of ALFALFA (Arecibo Legacy Fast ALFA) galaxies with H I detections such that we can examine the relationship between H I content (gas fraction, H I deficiency) and galaxy location on the main sequence (MS) in these two contrasting environments. We derive for the first time an H I scaling relation for isolated galaxies using WISE stellar masses, and thereby establish a baseline predictor of H I content that can be used to assess the impact of environment on H I content when compared with samples of galaxies in different environments. We use this updated relation to determine the H I deficiency of both our paired and isolated galaxies. Across all the quantities examined as a function of environment in this work (MS location, gas fraction, and H I deficiency), the AMIGA sample of isolated galaxies is found to have the lower dispersion: σ AMIGA = 0.37 versus σ PAIRS = 0.55 on the MS, σ AMIGA = 0.44 versus σ PAIRS = 0.54 in gas fraction, and σ AMIGA = 0.28 versus σ PAIRS = 0.34 in H I deficiency. We also note fewer isolated quiescent galaxies, 3 (0.6 per cent), compared to 12 (2.3 per cent) quiescent pair members. Our results suggest the differences in scatter measured between our samples are environment driven. Galaxies in isolation behave relatively predictably, and galaxies in more densely populated environments adopt a more stochastic behaviour, across a broad range of quantities. © 2020 The Author(s) ; This work is based on the research supported in part by the National Research Foundation of South Africa (Grant Numbers UID: 101099 and 111745). JB additionally acknowledges support from the DST-NRF Professional Development Programme (PDP), and the University of Cape Town. MEC is a recipient of an Australian Research Council Future Fellowship (project number FT170100273) funded by the Australian Government. THJ acknowledges funding from the National Research Foundation under the Research Career Advancement and South African Research Chair Initiative programmes, respectively. We acknowledge the work of the entire ALFALFA team for observing, flagging, and performing signal extraction. MGJ is supported by a Juan de la Cierva formaci?n fellowship (FJCI-2016-29685) from the Spanish Ministerio de Ciencia, Innovaci?n y Universidades (MCIU). MGJ also acknowledges support from the grants AYA2015-65973-C3-1- R (MINECO/FEDER, UE) and RTI2018-096228-BC31 (MCIU). This work has been supported by the State Agency for Research of the Spanish MCIU through the 'Centro de Excelencia Severo Ochoa' award to the Instituto de Astrof?sica de Andaluc?a (SEV-2017-0709). This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This work also utilizes data from Arecibo Legacy Fast ALFA (ALFALFA) survey data set obtained with the Arecibo L-band Feed Array (ALFA) on the Arecibo 305-m telescope. Arecibo Observatory is part of the National Astronomy and Ionosphere Center, which is operated by Cornell University under Cooperative Agreement with the U.S. National Science Foundation. Funding for the SDSS and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the U.S. Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England. The SDSS Web Site is http://www.sdss.org/. In addition, we make use of data from the Sloan Digital Sky Survey (SDSS DR7). The SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions. The Participating Institutions are the American Museum of Natural History, Astrophysical Institute Potsdam, University of Basel, University of Cambridge, Case Western Reserve University, University of Chicago, Drexel University, Fermilab, the Institute for Advanced Study, the Japan Participation Group, Johns Hopkins University, the Joint Institute for Nuclear Astrophysics, the Kavli Institute for Particle Astrophysics and Cosmology, the Korean Scientist Group, the Chinese Academy of Sciences (LAMOST), Los Alamos National Laboratory, the Max-Planck-Institute for Astronomy (MPIA), the Max-Planck-Institute for Astrophysics (MPA), New Mexico State University, Ohio State University, University of Pittsburgh, University of Portsmouth, Princeton University, the United States Naval Observatory, and the University of Washington ; Peer reviewed

We thank the anonymous referee for a constructive and detailed report. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement No 893673. We acknowledge financial support from the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement No 721463 to the SUNDIAL ITN network, from the State Research Agency (AEI-MCINN) of the Spanish Ministry of Science and Innovation under the grant "The structure and evolution of galaxies and their central regions" with reference PID2019-105602GBI00/10.13039/501100011033, and from IAC project P/300724, financed by the Ministry of Science and Innovation, through the State Budget and by the Canary Islands Department of Economy, Knowledge and Employment, through the Regional Budget of the Autonomous Community. SDG acknowledges support from the Spanish Public Employment Service (SEPE). Furthermore, we acknowledge support by the research project AYA2017-84897-P from the Spanish Ministerio de Economia y Competitividad, from the European Regional Development Funds (FEDER) and the Junta de Andalucia (Spain) grants FQM108. DE acknowledges support from a Beatriz Galindo senior fellowship (BG20/00224) from the Ministry of Science and Innovation. LVM acknowledges financial support from the grants AYA2015-65973-C3-1-R and RTI2018096228-B-C31 (MINECO/FEDER, UE), as well as from the State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709). This research makes use of python (http://www.python.org), Matplotlib (Hunter 2007), and Astropy (Astropy Collaboration 2013, 2018). We acknowledge the usage of the HyperLeda database (http://leda.univ-lyon1.fr).We thank Alexandre Bouquin for providing us with the GALEX FUV and NUV images used in this work. We thank Stephane Courteau, Estrella Florido, Raul Infante-Sainz, Tom Jarrett, Johan H. Knapen, Heikki Salo, and Miguel Querejeta for useful discussions. We thank Sebastien Comeron and Facundo D. Moyano for valuable comments on the manuscript. Facilities: GALEX, WISE, Spitzer (IRAC). ; Context. While some galactic bars show recent massive star formation (SF) along them, some others do not. Whether bars with low level of SF are a consequence of low star formation efficiency, low gas inflow rate, or dynamical effects remains a matter of debate. Aims. In order to study the physical conditions that enable or prevent SF, we perform a multi-wavelength analysis of 12 strongly barred galaxies with total stellar masses log(10)(M-*/M-circle dot)is an element of[10.2,11], chosen to host different degrees of SF along the bar major axis without any prior condition on gas content. We observe the CO(1-0) and CO(2-1) emission within bars with the IRAM-30 m telescope (beam sizes of 1.7-3.9 kpc and 0.9-2.0 kpc, respectively; 7-8 pointings per galaxy on average). Methods. We estimated molecular gas masses (M-mol) from the CO(1-0) and CO(2-1) emissions. SF rates (SFRs) were calculated from GALEX near-ultraviolet (UV) and WISE 12 mu m images within the beam-pointings, covering the full bar extent (SFRs were also derived from far-UV and 22 mu m). Results. We detect molecular gas along the bars of all probed galaxies. Molecular gas and SFR surface densities span the ranges log(10)(sigma(mol)/[M-circle dot pc(-2)]) is an element of [0.4,2.4] and log(10)(sigma(SFR)/[M-circle dot pc(-1) kpc(-2)]]) is an element of [-3.25, -0.75], respectively. The star formation efficiency (SFE; i.e., SFR/M-mol) in bars varies between galaxies by up to an order of magnitude (SFE is an element of[0.1,1.8] Gyr(-1)). On average, SFEs are roughly constant along bars. SFEs are not significantly different from the mean value in spiral galaxies reported in the literature (similar to 0.43 Gyr(-1)), regardless of whether we estimate M-mol from CO(1-0) or CO(2-1). Interestingly, the higher the total stellar mass of the host galaxy, the lower the SFE within their bars. In particular, the two galaxies in our sample with the lowest SFE and sigma(SFR) (NGC 4548 and NGC 5850, SFE less than or similar to 0.25 Gyr(-1), sigma(SFR)less than or similar to 10(-2.25)M(circle dot) yr(-1) kpc(-2), M greater than or similar to 10(10.7)M(circle dot)) are also those hosting massive bulges and signs of past interactions with nearby companions. Conclusions. We present a statistical analysis of the SFE in bars for a sample of 12 galaxies. The SFE in strong bars is not systematically inhibited (either in the central, middle, or end parts of the bar). Both environmental and internal quenching are likely responsible for the lowest SFEs reported in this work. ; European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie 893673 ; European Commission 721463 ; State Research Agency (AEI-MCINN) of the Spanish Ministry of Science and Innovation under the grant "The structure and evolution of galaxies and their central regions" - Ministry of Science and Innovation P/300724 PID2019-105602GBI00 ; Spanish Public Employment Service (SEPE) ; Spanish Ministerio de Economia y Competitividad, from the European Regional Development Funds (FEDER) AYA2017-84897-P ; Junta de Andalucia ; European Commission FQM108 ; Spanish Government BG20/00224 ; State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa award SEV-2017-0709 ; Canary Islands Department of Economy, Knowledge and Employment, through the Regional Budget of the Autonomous Community ; MINECO/FEDER, UE AYA2015-65973-C3-1-R RTI2018096228-B-C31

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. ; The Square Kilometre Array Observatory (SKAO) will build the most sensitive radio telescopes on Earth. To address fundamental questions in astrophysics, fundamental physics, and astrobiology, it will require processing and handling complex and extremely massive data close to the exascale, hence constituting a technological challenge for the next decade. Approximately 600 Peta-bytes (PB) of calibrated data will be delivered to the network of SKA Regional Centers (SRCs) worldwide. As a world-leading scientific instrument, SKAO aims to pursue the best practices in scientific methodology. Remarkably, it includes the reproducibility of its data as a metric of success. We present the Spanish prototype of an SRC (SPSRC), which supports preparatory scientific activities for the future SKA projects. These include science with SKA precursors and pathfinders while promoting Open Science practices as a way to enable scientific reproducibility. We describe the key developments and components of the SPSRC that align with these objectives. In particular, we describe the performed work on hardware and cloud computing infrastructure, science archive, software and services, user support and training, and collaboration with other SRCs. The resulting SPSRC platform is flexible enough to host heterogeneous projects while being scalable toward the demanding SKA requirements. © The Authors. Published by SPIE. ; We acknowledge financial support from the State Agency for Research of the Spanish Ministry of Science, Innovation and Universities through the "Center of Excellence Severo Ochoa" awarded to the Instituto de Astrofísica de Andalucía (SEV-2017-0709) and from the Grant no. RTI2018-096228-B-C31 (Ministry of Science, Innovation and Universities/State Agency for Research/European Regional Development Funds, European Union). In addition, we acknowledge financial support from the Ministry of Science, Innovation and Universities and the European Regional Development Funds (EQC2019-005707-P) and the Regional Government of Andalusia (SOMM17-5208-IAA-2017). LVM, JG, SSE and SLV acknowledge The European Science Cluster of Astronomy and Particle Physics ESFRI Research Infrastructures project that has received funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 824064. We would like to explicitly acknowledge Dr. José Ruedas, head of the Computer Centre at IAA-CSIC, for his technical assistance. We acknowledge the contribution from Theresa Wiegert. LVM, SSE, and SLV acknowledge financial support from the Grant No. COOPB20448 (Spanish National Research Council Program of Scientific Cooperation for Development i-COOP+2019). LVM, JG, and JM acknowledge financial support from the Grant No. RED2018-102587-T (Spanish Ministry of Science, Innovation and Universities/State Agency for Research). LVM, JG, SSE, JM acknowledge financial support from the Grant No. IAA4SKA P18-RT-3082 (Regional Government of Andalusia). LVM acknowledges financial support from the Ministry of Science and Innovation, from the budgetary line 28.06.000x.430.09 of the General State Budgets of 2021, for the coordination of the participation in SKA-SPAIN. LD acknowledges financial support from the Grant No. PTA2018-015980-I (Ministry of Science, Innovation and Universities and the Spanish National Research Council). MP acknowledges financial support from the Grant No. 54A Scientific Research and Innovation Program (Regional Council of Economy, Knowledge, Business and Universities, Regional Government of Andalusia and the European Regional Development Funds 2014-2020, program D1113102E3).

Context. While some galactic bars show recent massive star formation (SF) along them, some others do not. Whether bars with low level of SF are a consequence of low star formation efficiency, low gas inflow rate, or dynamical effects remains a matter of debate. Aims. In order to study the physical conditions that enable or prevent SF, we perform a multi-wavelength analysis of 12 strongly barred galaxies with total stellar masses log10(M⊙/M⊙)? [10.2, 11], chosen to host different degrees of SF along the bar major axis without any prior condition on gas content. We observe the CO(1-0) and CO(2-1) emission within bars with the IRAM-30 m telescope (beam sizes of 1.7-3.9 kpc and 0.9-2.0 kpc, respectively; 7-8 pointings per galaxy on average). Methods. We estimated molecular gas masses (Mmol) from the CO(1-0) and CO(2-1) emissions. SF rates (SFRs) were calculated from GALEX near-ultraviolet (UV) and WISE 12 μm images within the beam-pointings, covering the full bar extent (SFRs were also derived from far-UV and 22 μm). Results. We detect molecular gas along the bars of all probed galaxies. Molecular gas and SFR surface densities span the ranges log10(ςmol/[M⊙ pc-2]) ? [0.4,2.4] and log10(ςSFR/[M⊙ pc-1 kpc-2]]) ? [-3.25, -0.75], respectively. The star formation efficiency (SFE; i.e., SFR/Mmol) in bars varies between galaxies by up to an order of magnitude (SFE ? [0.1, 1.8] Gyr-1). On average, SFEs are roughly constant along bars. SFEs are not significantly different from the mean value in spiral galaxies reported in the literature (∼0.43 Gyr-1), regardless of whether we estimate Mmol from CO(1-0) or CO(2-1). Interestingly, the higher the total stellar mass of the host galaxy, the lower the SFE within their bars. In particular, the two galaxies in our sample with the lowest SFE and ςSFR (NGC 4548 and NGC 5850, SFE ? 0.25 Gyr-1, ςSFR ? 10-2.25 M⊙ yr-1 kpc-2, M⊙ ? 1010.7 M⊙) are also those hosting massive bulges and signs of past interactions with nearby companions. Conclusions. We present a statistical analysis of the SFE in bars for a sample of 12 galaxies. The SFE in strong bars is not systematically inhibited (either in the central, middle, or end parts of the bar). Both environmental and internal quenching are likely responsible for the lowest SFEs reported in this work. © ESO 2021. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement No 893673. We acknowledge financial support from the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement No 721463 to the SUNDIAL ITN network, from the State Research Agency (AEI-MCINN) of the Spanish Ministry of Science and Innovation under the grant "The structure and evolution of galaxies and their central regions" with reference PID2019-105602GB-I00/10.13039/501100011033, and from IAC project P/300724, financed by the Ministry of Science and Innovation, through the State Budget and by the Canary Islands Department of Economy, Knowledge and Employment, through the Regional Budget of the Autonomous Community. SDG acknowledges support from the Spanish Public Employment Service (SEPE). Furthermore, we acknowledge support by the research project AYA2017-84897-P from the Spanish Ministerio de Economia y Competitividad, from the European Regional Development Funds (FEDER) and the Junta de Andalucia (Spain) grants FQM108. DE acknowledges support from a Beatriz Galindo senior fellowship (BG20/00224) from the Ministry of Science and Innovation. LVM acknowledges financial support from the grants AYA2015-65973-C3-1-R and RTI2018-096228-B-C31 (MINECO/FEDER, UE), as well as from the State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709). This research makes use of python (http://www.python.org), Matplotlib (Hunter 2007), and Astropy (Astropy Collaboration 2013, 2018). We acknowledge the usage of the HyperLeda database (http://leda.univ-lyon1.fr). ; Peer reviewed

Contributions to the XIV.0 Scientific Meeting (virtual) of the Spanish Astronomical Society, held 13-15 July 2020, online at https://www.sea-astronomia.es/reunion-cientifica-2020, id.52 ; With funding from the Spanish government through the Severo Ochoa Centre of Excellence'accreditation SEV-2017-0709

Mergers of galaxies are an important mode for galaxy evolution because they serve as an efficient trigger of powerful starbursts. However, observational studies of molecular gas properties during their early stages are scarce. We present interferometric CO(2-1) maps of two luminous infrared galaxies, NGC 3110 and NGC 232, obtained with the Submillimeter Array with ∼1 kpc resolution. While NGC 3110 is a spiral galaxy interacting with a minor (14:1 stellar mass) companion, NGC 232 is interacting with a similarly sized object. We find that such interactions in these galaxies have likely induced enhancements in the molecular gas content and central concentrations, partly at the expense of atomic gas. The obtained molecular gas surface densities in their circumnuclear regions are Σ10 M pc, higher than in noninteracting objects by an order of magnitude. Gas depletion times of 0.5-1 Gyr are found for the different regions, lying in between noninteracting disk galaxies and the starburst sequence. In the case of NGC 3110, the spiral arms show on average 0.5 dex shorter depletion times than in the circumnuclear regions if we assume a similar H-CO conversion factor. We show that even in the early stages of the interaction with a minor companion, a starburst is formed along the circumnuclear region and spiral arms, where a large population of SSCs is found (∼350), and at the same time a large central gas concentration is building up that might be the fuel for an active galactic nucleus. The main morphological properties of the NGC 3110 system are reproduced by our numerical simulations and allow us to estimate that the current epoch of the interaction is at ∼150 Myr after closest approach.© 2018. The American Astronomical Society. All rights reserved. ; We thank the referee for the careful reading and valuable suggestions that helped to improve this paper substantially. This research made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. We acknowledge the usage of the HyperLeda database. (http://leda.univ-lyon1.fr). We thank Dr. T. Hattori and Dr. H. Schmitt for kindly providing Ha maps used in this paper to derive the SF laws. D.E. was supported by a Marie Curie International Fellowship within the Sixth European Community Framework Programme (MOIF-CT-2006-40298). S.V. acknowledges support by the research projects AYA2014-53506-P and AYA2017-84897-P from the Spanish Ministerio de Economia y Competitividad, from the European Regional Development Funds (FEDER) and the Junta de Andalucia (Spain) grants FQM108. T.S. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 694343). L.V.M. acknowledges support from the grant AYA2015-65973-C3-1-R (MINECO/FEDER, UE). S. Matsushita is supported by the Ministry of Science and Technology (MOST) of Taiwan, MOST 106-2112-M-001-011 and 107-2119-M-001-020. M.A.F. is grateful for financial support from the CONICYT Astronomy Program CAS-CONICYT project No. CAS17002, sponsored by the Chinese Academy of Sciences (CAS), through a grant to the CAS South America Center for Astronomy (CASSACA) in Santiago, Chile. This research made use of Astropy, a community-developed core Python. (http://www.python.org) package for Astronomy (Astropy Collaboration et al. 2013; The Astropy Collaboration et al. 2018); ipython (Perez & Granger 2007); matplotlib (Hunter 2007); APLpy, an opensource plotting package for Python (Robitaille & Bressert 2012) and NumPy (Van Der Walt et al. 2011). We utilized the pynbody python package (Pontzen et al. 2013) for post-processing and analyzing of the tipsy files created by gasoline2. Special thanks to the authors of gasoline2 (Wadsley et al. 2017) for providing the numerical code used to perform the simulations. Part of this work was achieved using the grant of Visiting Scholars Program supported by the Research Coordination Committee, National Astronomical Observatory of Japan (NAOJ), National Institutes of Natural Sciences (NINS). D. E. was supported by JSPS KAKENHI grant No. JP 17K14254.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. ; We study the tidal interaction of galaxies in the Eridanus supergroup, using H i data from the pre-pilot survey of the Widefield ASKAP L-band Legacy All-sky Blind surveY. We obtain optical photometric measurements and quantify the strength of tidal perturbation using a tidal parameter Ssum. For low-mass galaxies of M* ≲ 109 M⊙, we find a dependence of decreasing H i to optical disk size ratio with increasing Ssum, but no dependence of H i spectral line asymmetry with Ssum. This is consistent with the behavior expected under tidal stripping. We confirm that the color profile shape and color gradient depend on the stellar mass, but there is an additional correlation of low-mass galaxies having their color gradients within 2R50 increasing with higher Ssum. For these low-mass galaxies, the dependence of color gradients on Ssum is driven by the color becoming progressively redder in the inner disk when tidal perturbations are stronger. For high-mass galaxies, there is no dependence of color gradients on Ssum, and we find a marginal reddening throughout the disks with increasing Ssum. Our result highlights tidal interaction as an important environmental effect in producing the faint end of the star formation suppressed sequence in galaxy groups. © 2022. The Author(s). Published by the American Astronomical Society. ; J.W. acknowledges support from the National Science Foundation of China (12073002 and 11721303), and the science research grants from the China Manned Space Project with No. CMS-CSST-2021-B02. Parts of this research were supported by High-performance Computing Platform of Peking University. F.B. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program ...