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Who Publishes A&A?

Posted in Euclid, Open Access with tags Astronomy and Astrophysics, China Science Publishing & Media, EDP Sciences, European Southern Observatory, Open Access Publishing, Open Access Publishing., S20, Subscribe to Open on May 8, 2024 by telescoper

The journal Astronomy & Astrophysics, generally known as A&A, which featured in yesterday’s post, is and has been for some time the journal of choice for many astrophysics researchers, especially those based in Europe. It is the journal in which the bulk of publications from Euclid will be published, including a batch due to come out in a couple of weeks.

The journal, which has existed since 1969, is published on behalf of the European Southern Observatory by EDP Sciences (Édition Diffusion Presse Sciences) which began life as a joint venture of four French learned societies in science, mathematics, and medicine. The company was acquired in 2019 by China Science Publishing & Media (which has headquarters in Beijing). Judging by its social media activity, EDP Sciences sees A&A as a flagship journal; for a list of other journals it runs see here.

A&A publishes papers through a curious hybrid model called “S2O” (Subscribe to Open; not to be confused with “420”). This is not fully Open Access because it requires libraries to pay a subscription to access the journal, but unlike some journals A&A does allow authors to place their papers on arXiv without restriction, so they can be read there for free. On the other hand, A&A also requires authors to pay “Page Charges” – essentially an Article Processing Charge (APC) – if they are not from a “member country”. Authors from a member country do not have to pay APCs to publish but their institutional libraries still have to pay a subscription if they are to access the paper.

You might ask why you should publish in A&A if you can put your papers on arXiv. The answer given on the website is:

Preprint servers such as arXiv play a vital role in bringing research into the astronomy and astrophysics communities as quickly as possible. However, content uploaded to this service has not undergone rigorous peer review and the editorial oversight offered by a professional publisher such as EDP Sciences. In addition, preprints don’t offer the content selection and curation processes that make a scholarly journal a reliable and trusted addition to library collections.

In summary, publishing your article in A&A increases the value and impact of your work by making your article more trustworthy, easier to find, read, and cite, whilst ensuring that the version of record is preserved in perpetuity.

In other words, A&A does nothing that the Open Journal of Astrophysics doesn’t do for free…

Incidentally, I am struck by the frequent assertion that publishers preserve or curate content. Actually they don’t. Libraries do that. If a publisher such as EDP Science decides a journal is no longer commercially viable it will simply ditch it. Fortunately nowadays institutions maintain their own repositories of published papers as insurance against this.

Here is some more information about how S20 works, taken from the A&A website:

A&A is a community journal sponsored by a board of member countries. While subscriptions fund the publishing costs of the journal, the editorial costs are funded both by the contributions from member countries, and the page charges for authors of non-member countries. This division of costs between authors and readers makes it possible to offer low subscription prices, while at the same time removing barriers to publishing for authors from A&A sponsoring countries, and allowing authors from non-sponsoring countries to publish for a modest charge.

If the S2O model is successful, editorial costs will continue to be funded by A&A member contributions and page charges, while subscriptions will be used to cover the open access publication of the journal. Authors from sponsoring countries can therefore publish in open access free of charge, while authors from other countries remain liable for page charges to fund the editorial process of their article (note: page charges are paid to A&A directly and not to the publisher).

This arrangement is being kept under annual review so whether it will persist is open to question.

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.Astronomy

Posted in Barcelona, Euclid, The Universe and Stuff with tags astronomy, dotastronomy, ESAC, ESOC, Euclid, European Space Agency, European Space Astronomy Centre, European Space Operations Centre, Madrid on April 24, 2024 by telescoper

So here I am at the European Space Astronomy Centre (ESAC) just outside Madrid for a conference called .Astronomy 13. It is (obviously) the thirteenth such conference but the first that I have attended. I’m giving a plenary talk in half-an-hour or so. I travelled from Barcelona by train yesterday evening, which was a comfortable and uneventful trip, the (approximately) 504 km from Barcelona to Madrid Atocha station taking about 2 hours and 30 minutes that cost about 30 euros. I stayed overnight in Madrid and took a shuttle bus from to ESAC. The only glitch in my travels so far was that I got on the Metro Line 6 (the equivalent of the Circle Line), but chose the wrong platform and went the long way round. I still got there in time to get the shuttle.

Incidentally, ESAC hosts the Euclid Science Operations Centre (SOC) which plays a central role in the processing of data from Euclid and is also responsible for the development and operations of the Euclid Archive from which data will be distributed to the global astronomical community.

UPDATE: Back in Barcelona. The return by train was just as smooth an uneventful as the outbound journey, and in fact arrived back about five minutes ahead of schedule. Thanks to the organizers for inviting me – I’m sorry I couldn’t stay for longer as I like the idea of the .Astronomy meetings. Perhaps we should have one in Ireland sometime?

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The Inaugural Euclid Spain Meeting

Posted in Barcelona, Euclid, The Universe and Stuff with tags Barcelona, Euclid, Institut de Ciencies de L'Espai, UAB, Universidad Autónoma de Barcelona on April 18, 2024 by telescoper

So here I am at the Institut de Ciencies de L’Espai (ICE-CSIC) which is on the campus of the Universidad Autónoma de Barcelona (UAB) for the first ever Euclid Spain Meeting. This involved a 40-minute trip on the S2 train from Plaça de Catalunya, which is a short walk from my apartment, then a short walk from the railway station at UAB through the campus to the Institute.

I was able to speak at this meeting because I happen to be in Barcelona right now. I mean that I was able to attend because I was in Barcelona anyway, not that the meeting was held because I am in Barcelona!

Anyway, I gave my talk early on this morning, so have been able to enjoy the rest of the day having got that out of the way. There are about 50 people here. It’s great to see the sizable Euclid community in Spain getting together and sharing their work.

The Inaugural Euclid Spain Meeting

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P.S. My surname always causes some amusement in Spain, as “Coles” means “Cabbages” in Spanish…

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DESI Year 1 Results: Baryon Acoustic Oscillations

Posted in Barcelona, Euclid, The Universe and Stuff with tags baryon acoustic oscillations, Cosmology, Dark Energy Spectroscopic Instrument, DESI, Hubble Tension on April 4, 2024 by telescoper

There has been a lot of excitement around the ICCUB today – the press have been here and everything – ahead of the release of the Year 1 results from the Dark Energy Spectroscopic Instrument (DESI). The press release from the Lawrence Berkeley Laboratory in California can be found here.

The papers were just released at 5pm CEST and can be found here. The key results pertain to Baryon Acoustic Oscillations (BAOs) which can be used to track the expansion rate and geometry of the Universe. This is one of the techniques that will be used by Euclid.

There’s a lot of technical information to go through and I have to leave fairly soon. Fortunately we have seminar tomorrow that will explain everything at a level I can understand:

I will update this post with a bit more after the talk, but for the time being I direct you to the high-level cosmological implications are discussed in this paper (which is Paper VI from DESI).

If your main interest is in the Hubble Tension then I direct you to this Figure:

Depending on the other data sets included, the value obtained is around 68.5 ± 0.7 in the usual units, closer to the (lower) Planck CMB value than the (higher) Supernovae values but not exactly in agreement; the error bars are quite small too.

You might want to read my thoughts about distances estimated from angular diameters compared with distances measured using luminosity distances here.

If you’re wondering whether there is any evidence for departures from the standard cosmology, another pertinent comment is:

In summary, DESI data, both alone and in combination with other cosmological probes, do not show any evidence for a constant equation of state parameter different from −1 when a flat wCDM model is assumed.
DESI 2024 VI: Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations

More complicated models of time-varying dark energy might work, but there’s no strong evidence from the current data.

That’s all from me for now, but feel free to comment through the box below with any hot takes!

UPDATE: As expected there has been quite a lot of press coverage about this – see the examples below – mostly concentrating on the alleged evidence for “new physics”. Personally I think the old physics is fine!

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Euclid on Ice

Posted in Euclid, The Universe and Stuff with tags dark matter, ESA, Euclid, European Space Agency, Ice, Science, Universe on March 25, 2024 by telescoper

I thought it would be appropriate to add a little update about the European Space Agency’s Euclid mission. I’ll keep it brief here because you can read the full story on the official website here.

You may have seen in the news that the Euclid telescope has been having an issue with ice forming on surfaces in its optical systems, especially the VIS instrument. This is a common problem with telescopes in space, but the extent of it is not something that can be predicted very accurately in advance so a detailed strategy for dealing with it had to be developed on the go.

The layers of ice that form are very thin – just tens of nanometres thick – but that is enough to blur the images and also reduce the throughput of the instruments. Given that the objects we want Euclid to see are faint, and we need very sharp images then this is an issue that must be dealt with.

Soon after launch, the telescope was heated up for a while in order to evaporate as much ice as possible, but it was not known how quickly the ice would return and to what parts of the optical system. After months in the cold of space the instrument scientists now understand the behaviour of the pesky ice a lot better, and have devised a strategy for dealing with it.

The approach is fairly simple in principle: heat the affected instruments up every now and again, and then let them cool down again so they operate; repeat as necessary as ice forms again. This involves an interruption in observations, it is known to work pretty well, but exactly how frequently this de-icing cycle should be implemented and what parts of the optical system require this treatment are questions that need to be answered in practical experimentation. The hope is that after a number of operations of this kind, the amount of ice returning each time will gradually reduce. I am not an expert in these things but I gather from colleagues that the signs are encouraging.

For more details, see here.

UPDATE: The latest news is that the de-icing procedure has worked better than expected! There’s even a video about the result of the process here:

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The Euclid Survey(s)

Posted in Euclid, The Universe and Stuff with tags astronomy, Euclid, Euclid Deep Field Fornax, Euclid Deep Field North, Euclid Deep Field South, Euclid Deep Fields, European Space Agency, NASA, Science, Wide Survey on February 27, 2024 by telescoper

Since it’s been a couple of weeks since Euclid commenced its routine survey operations, I thought I would share this little video from the European Space Agency that shows how the surveying will proceed over the next six years with explanatory text adapted from here:

This animation shows the location of the fields on the sky that will be covered by Euclid’s wide (blue) and deep (yellow) surveys. The sky is shown in the Galactic coordinate system, with the bright horizontal band corresponding to the plane of our Milky Way.

The wide survey will cover more than one third of the sky as shown in blue. Other regions are avoided because they are dominated by Milky Way stars and interstellar matter, or by diffuse dust in the Solar System – the so-called zodiacal light. The wide survey is complemented by a deep survey, taking about 10% of the total observing time and repeatedly observing just three patches of the sky called the Euclid Deep Fields, highlighted in yellow.

The Euclid Deep Field North – towards the top left – has an area of 20 square degrees and is located very close to the Northern Ecliptic Pole. The proximity to the ecliptic pole ensures maximum coverage throughout the year; the exact position was chosen to obtain maximum overlap with one of the deep fields surveyed by NASA’s Spitzer Space Telescope.

The Euclid Deep Field Fornax – in the lower right of the image – spans 10 square degrees and is located in the southern constellation Fornax, the furnace. It encompasses the much smaller Chandra Deep Field South, a 0.11 square degree region of the sky that has been extensively surveyed in the past couple of decades with the Chandra and XMM-Newton X-ray observatories, as well as the Hubble Space Telescope and major ground-based telescopes.

The third and largest of the fields is the Euclid Deep Field South – between the Large Magellanic Cloud and the Euclid Deep Field Fornax. It covers 20 square degrees in the southern constellation of Horologium, the pendulum clock. This field has not been covered to date by any deep sky survey and so has a huge potential for new, exciting discoveries. It has been planned to be observed from the ground by the Vera C. Rubin Observatory.

P.S. According to my latest calculations, I shall have retired by the time the Wide survey is completed.

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Euclid Update

Posted in Euclid, History, The Universe and Stuff on February 13, 2024 by telescoper

It’s a lovely sunny Saint Ash Valentine’s Wednesday Day in Australia though I’m not sure what day it is at the 2nd Lagrange Point of the Earth-Sun system. Nevertheless, as I mentioned last week, Euclid’s Wide Survey starts today; here is the official announcement of this from ESA. To mark this momentous event here is another nice video update showing the preparations that have been going on ahead of the arrival of the deluge of real data:

Among other things, you will see an appearance by Henry Joy McCracken whose namesake led the United Irishmen in the Rebellion of 1798.

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A Euclid Milestone!

Posted in Euclid, The Universe and Stuff with tags dark matter, Deep Survey, Euclid, Euclid Consortium, Science Data Centre, Science Ground Segment, SDC, SGS, Wide Survey on February 9, 2024 by telescoper

I just heard some excellent news about Euclid so thought I would post a quick update here. I won’t say much because there will no doubt be official communications from the European Space Agency and the Euclid Consortium. You can find a variety of Euclid-related posts on this blog here.

Over the past few months, there has been a huge amount of activity relating to commissioning the instruments, verifying their performance, and measuring parameters of the optical system that will be needed for analysis of the huge amount of data due to come from Euclid. All this effort fed into the Mission Commissioning Results Review (MCRR) which concluded yesterday that all was well.

This is an important milestone for Euclid because, in ESA parlance, it marks the change from a project to a mission. Until commissioning, there is a project manager who works with ESA and the industrial contractors to ensure everything functions properly; when nominal operations start the project team is disbanded and the mission team takes over; and so it came to pass that the Project Manager (Giuseppe Racca) handed over the reins to the Mission Manager (Pierre Ferruit).

That’s when the role of the Euclid Consortium increases substantially. In particular the Science Ground Segment (SGS), which includes the pipelines that will process the data, has been declared to be ready for business. You can read more about the SGS here but here’s a graphic that shows how data comes from the telescope, external telescopes, or simulations, then run through their respective pipelines for VIS, NISP, or external data, then are merged into a coherent format. Pipelines then extract scientific information and compute science data products for further analysis

Each element of this diagram is rather complex. Here, for example, is the organization of the Science Data Centre (SDC) component of the Science Ground Segment at the bottom of the above picture, consisting of computing centers responsible for implementing and running the data processing pipelines:

Anyway, the immediate upshot of all this is that full surveying activities of Euclid can now proceed. The Euclid mission will conduct primarily two different surveys: a “Wide Survey”, covering about 15,000 square degrees on the sky, and a “Deep Survey” of about 50 square degrees, where the instruments will observe three fields much longer than the rest of the sky to capture much fainter galaxies and hence look further out into space. I understand that the Wide Survey will commence in earnest on 14th February.The timescale from now is that the first full set of survey data (DR1) will be available internally to the Euclid Consortium in May or June 2025 and will be made public a year later (i.e. by June 2026).

That doesn’t mean that Euclid will be silent until 2026. In fact, the first batch of post-launch papers will come out very soon, in May 2024. This will include science papers resulting from the Early Release Observations – the data from these will also be made public at the same time – as well as an overview paper for the whole mission and papers describing the details of NISP and VIS instruments using measurements made during commissioning. There will also be a release in May 2025 of data from the Deep Survey patch of about 50 square degrees.

So, the board is set. The pieces are moving.

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The Little Book of Irish Research

Posted in Euclid, Maynooth, The Universe and Stuff with tags Little Book of Irish Research, research on January 30, 2024 by telescoper

A few months ago, I blogged on the occasion of the launch by Simon Harris TD, Minister for Further and Higher Education, Research, Innovation and Science, of the Little Book of Irish Research. This book, which is aimed at school students, so is written at an elementary level, gives quick summaries of areas of research that the general public said that they were interested in, grouped into sixteen themes, and it will be distributed to schools all round Ireland.

if you want to read it here is a PDF file of the whole thing for you to download at your leisure. When I posted about it last time I hadn’t actually seen a hard copy, but I finally got my hands on one:

I can now confirm that it is indeed a little book. I think we’ll find it useful for our own outreach events, open days, etc, in the Department of Theoretical Physics, and so will the many colleagues in other Departments in other universities and research institutes whose work is also featured.

I was very gratified to see myself get a mention (on page 41), though it’s not really about me but about Euclid which has generated considerable interest in the general public already and is set to continue doing that for many years. As you can see, there’s also a double-page spread of JWST, though unfortunately it does not name the scientists involved; Paddy Kavanagh is the main man at Maynooth for matters JWST.

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Euclid: a Year of Diversities

Posted in Biographical, Euclid, Maynooth with tags ECDC, Euclid, Euclid Consortium Diversity Committee, Phase Diversity, Zoom on December 28, 2023 by telescoper

I have now entered that strange twilight zone between Christmas and New Year during which it is difficult to remember which day is which, so I thought I’d just do a quick retrospective about the thing that has the biggest effect on my professional life in 2023, namely the Euclid satellite.

Euclid Consortium Meeting 2023 Conference Photograph

Euclid was launched halfway through the year, on July 1st, an event that took place just a week after or so after the annual Euclid Consortium Meeting in Copenhagen when I took over as Chair of the Euclid Consortium Diversity Committee. The latter led to a huge increase in the number of telecons I had to attend, not only the ECDC’s own bi-weekly Zoom meetings but also various other committees that the ECDC Chair attends ex officio. Much of the Chair’s work is confidential, which means there is no-one to consult with about the difficult matters. Had I not been on sabbatical since September I don’t think I would have had either the time or the energy to carry out these duties. It has taken me quite a while to get the hang of this role, but I do feel that it’s important and that I have contributed in a small way to the Euclid Consortium.

As for the scientific side of Euclid, after a few technical issues the commissioning of Euclid’s instruments is now more-or-less over and the final preparations are being made for the survey proper, which will take commence in the New Year. What is going on now is called a phase diversity analysis, which is being used to verify and improve the performance of the optical system.

In November, a set of Early Release Observations were published. Early in the New Year a number of scientific papers about these will be published, along with other papers about Euclid in general, including an overview paper that provides a high-level description of the mission. Data relating to the Early Release Observations will also be released to the general public.

After that the survey will begin in earnest. The full exercise will take six years to complete – I’ll have retired before it finishes – but there will be a first data release (DR1) using one year’s worth of survey data. That should give a good idea of how well it’s all going to work out for the full survey. That data will be made available to the public.

If all goes to plan, after the annual EC meeting (which next year will be in Rome, from 17th to 21st June), I’ll be stepping down as ECDC Chair and indeed from the ECDC altogether. That is just as well because my sabbatical will be over at the end of August and I’ll be back to a full teaching and admin load at Maynooth, assuming there’s still a Department to return to!

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