Cool visualization

 Some members of IceCube (led by Lu Lu, at UW Madison) have created a cool new visualization for IceCube events.  It shows where the neutrinos that reach IceCube entered the Earth (only upward-going muon neutrinos are shown).  The Earth can be rotated, and it is possible to set the minimum energy.  These are mostly atmospheric neutrinos, so are distributed over the Earth, but it is still possible to see some interesting things.  

In the screen-capture above, with an energy threshold of 100 TeV, it is clear that the neutrinos are predominantly in the Southern hemisphere.   This is because, at these energies, most neutrinos are absorbed in the Earth, so, with their longer trajectories through the Earth, most Northern hemisphere neutrinos are absorbed before reaching IceCube.

More on Science in the age of Ukraine

 I wanted to give you an update on how international science (CERN, in particular) has been reacting to the continued Russian invasion of Ukraine.  The invasion is now in its 8th month, and the four large LHC experiments still have not decided how to publish papers with author lists, affiliations and acknowledgements of funding agencies that reflect that fact.  Papers from the LHC experiments are being sent to the Cornell arXiv with the authors listed as "The ALICE Collaboration," without lists of individual authors, institutional affiliations, or acknowledgements to the funding agencies. 

The papers are also being submitted to diverse scientific journals for review, with the understanding that versions with author lists, affiliations and acknowledgements will be forthcoming, hopefully allowing for timely publication.  Unfortunately, after 8 months, it is clear that the 'timely' part of this is not happening, and it is likely that some journals are becoming less happy about the situation.   They do best on a steady diet of publications.  It will not be easy for them to deal with a brief flood of manuscripts that are ready for publication once the author lists, etc. arrive.  

This will also not make things easier for some of our younger colleages who may be in the job market.  Everybody involved in CERN is well aware of the situation.  However, although the collaborations are making every effort to document their contributions, not having actual published papers may not make things easier farther afield, either in smaller institutions where one interviews with people in other subfields of physics, or in industry.

CERN, for its part, has not taken further visible action, with the last pronouncement being their March 8th announcement. 

A new source of astrophysical neutrinos

 

A likely new source of astrophysical neutrinos has been identified!  In a paper published in Science, the IceCube Collaboration reported on the observation of neutrinos coming from an object called NGC1068, with 4.1 sigma significance.  The probability that this is a random statistical fluctuation is about 1.1 in 100,000.  This calculated significance accounts for the fact that this was part of a search for neutrinos from 110 likely sources that were studied - this is known as correcting for trial factors - essentially the number of experiments that were tried at once.  A version of the paper is also available here, on the Cornell arXiv preprint server).

NGC1068 (also sometimes known as M77) is an Active Galactic Nucleus (AGN) about 47 million light years from Earth.  AGNs are spiral galaxies with supermassive black holes at their center.  These black holes accrete (pull in) matter from the surrounding galaxy; in the process, some of the matter is ejected at relativistic velocities (speeds a fair fraction of the speed of light) in a collimated jet that follows the axis of rotation of the galaxy.  NGC1068 is one of the closer AGNs, so it is not too surprising that it should be one of the first (after TXS0605+56) high-energy astrophysical neutrino sources to be observed.  The signal was composed of about 80 neutrinos over the background, which was mostly  atmospheric neutrinos. The figure above shows the position of the hotspot (including contours corresponding to 68% and 90% positional uncertainty) compared with that of NGC1068, denoted by the red star.   The agreement is good, and there are no other likely sources within the error contours.

NGC1068 was first seen in an earlier IceCube paper, published in 2020 in Physical Review Letters  (also freely available here, from the Cornell arXiv).   That paper used 10 years of data, and observed NGC1068 with a significance of 2.9 sigma.  The higher significance came from a couple of factors: more new data (and some old partial-detector data was dropped), improved calibrations, and an improved analysis method.  Going from 2.9 sigma to  4.1 sigma is a pretty significant improvement for a re-analysis like this; it seems that the largest single factor was the improved calibrations.

Assuming that this holds up (it is not over the 5 sigma threshold ), this will be the second neutrino source seen by IceCube.  Both are AGNs, so those of us who are impatient can see a pattern developing.  That said, there are differences.  TXS0506 is much further away  - 5.6 billion light years.   It is a known source of gamma-rays, while NGC1068 is not - it's jet is surrounded by a dust cloud that would obscure X-rays and gamma-rays.  And, neutrino emission from TXS0506 was associated with a period exhibiting an increase in gamma-rays, while the NGC1068 source is steady state (at least we have not seen evidence for variability).

STAR Trek medicine: coming soon to a doctor near you?

Star Trek is full of cool science-fictiony gadgets, most of which are far beyond the understanding of todays science.    Today, I wanted to write about a new development that now seems related to one of these devices - Star Trek's dermal regenerator.  Dermal regenerators are hand held devices that can be held over cuts, wounds, burns etc. to repair the damage.   Now, a paper in Science magazine has reported on a technique that is at least a small step in that direction.  The paper is Z. Ma et al., Science 377, 751 (2022); unfortunately, Science has a new system for subscribers that defeats my ability to provide a URL.

Today, surgeons seal incisions (either surgical or wounds) using sewing (stitches) or staples.  It works, but is inelegant, and since it involves additional piercing of the skin around the wound, it causes some additional damage.   A worthwhile tradeoff, but not optimal, so doctors have been searching for an alternative.

Adhesives are one obvious alternative, but they have unfortunate limitations which have prevented their use.  In short, living tissue is wet, slippery and pliable - three factors that are difficult for glues.  Pliability is a special problem, since it requires an adhesive that is equally pliable - even after setting.  Otherwise, when the recipient moves, the wound will tear open again. So far, no workable option has been found.  

Now, the Science paper presents a method of using ultrasound to get adhesives to set quickly and strongly.  It starts by adding a solution containing polymers to the wound.  Polymers are long-chain hdyrocarbons that have a tendency to cross-bond with each other.  Think plastics.  This is followed by a hydrogel.  Then, ultrasound is applied - this is where a dermal regenerator  like device comes in - this could be a hand held unit waved over the wound.  The ultrasound performs a couple of functions.  It drives the polymers deeper into the wound.  And, it causes them to spread out and cross-link, forming a strong but flexible network to hold the wound together.  Voila - Star Trek in the 21st century.

It turns out that I am not the only one to make the connection between recent medical developments and a dermal regenerator.  Julia Simpson wrote about some different possible approaches toward a dermal regenerator about a year ago.   She proposed three possibilities, all of which involve adding something to the wound: a matrix of silkworm and spider silk, a specially made biomaterial, and a hydrogel scaffold that would alter the immune system to improve healing.  However, none of these seem to require a handheld device - the need for ultrasound makes this new development closer to a true dermal regenerator.  Another approach, which seems closer to that depicted in Star Trek, would be to use a bioprinter to essentially print replacement tissue to fill in the wound.  

Of course, all of these ideas are quite some distance from routine use in a doctors office or hospital.   And, I should note that I am not a medical doctor, so take this with a grain of salt (or, this being Star Trek, a grain of quadrotriticale).   But, it seems like a really cool idea, and hopefully it will pan out.

Imaging the Earth with Neutrinos

 Hi again,

As the Russian invasion of Ukraine continues (with, to my mind, uncertain results), the four CERN LHC experiments still have no agreement on papers with Russian co-authors.  Since early March (6 months ago), the experiments have been submitting papers to the Cornell preprint server with only collaboration names - no individual authors.   These 'nameless' papers are being refereed by journals, and doubtless some of them are ready for publication, lacking only a specific list of author names, and likely affiliations.  

The world of neutrino astronomy has also been pretty quiet.   The RNO-G deployment season in Greenland is winding down, apparently quite successful.  There was an interesting two-day (Saturday and Sunday) meeting at "NuFact 2022" on the use of neutrinos to image the interior of the Earth.  There are two techniques that can be used.  The first is to look for neutrino absorption in the Earth, as we have discussed before.  The second is to study neutrino interactions with the electrons in the nuclei in the Earth.  These electrons are seen as effectively a large cloud, and electron-flavored neutrinos interact with the cloud differently than muon-flavored and tau-flavored neutrinos.  This affects how neutrinos oscillation - this is known as matter-induced oscillations.   The affect depends on the electron density, so oscillations can serve as a complementary approach to neutrino absorption.

Ukraine, Russia and Astrophysics

My posts about scientists' response to the Russian invasion of Ukraine have been mostly focused on particle physics, since CERN has notably struggled to craft an appropriate response.  Nowhere else is the conflict between science as a driver of international cooperation, and the need to stand up against an immoral invasion so stark.    

But, other physicists have also faced conflicts over this.  In high-energy neutrino astrophysics, there was less collaboration between Russian and Western scientists, but there were still many discussions about appropriate responses.  

IceCube had no members whose primary affiliation was Russian.  Two IceCube physicists had secondary affiliations with Moscow Engineering Physics Institute, but they both dropped these connections shortly after the invasion.   

The Baikal-GVD experiment (in Lake Baikal) was almost entirely Russian collaborators.  Some long-time collaborators from what used to be East Germany dropped out.   Both the Baikal-GVD and IceCube responses were made relatively quietly. 

In contrast, the mostly-European KM3NeT collaboration (building two arrays in the Mediterranean) has taken a public stance.  They have had Russian collaborators in past years, but do not appear to do so now.  Nevertheless, they made a clear statement to #StandwithUkraine, suspending all institutional cooperation with science organizations in Russia.   Their statement, highlighted on their main web page is nicely nuanced, continuing "We deeply believe that science is to serve peace and understanding, and we therefore leave private communication channels open to our colleagues with Russian affiliation, of whom many have stood up against the war." 

 

 Photo: a KM3NeT string, waiting for deployment.  Credit: KM3NeT Collaboration.

 

The Global Neutrino Networks newsletter, edited by Christian Spiering (from DESY-Zeuthen, near Berlin)  has done a very nice job of covering the astrophysicists response to the Russian invasion.  Back issues of the newsletter are available here.

CERN and Russia break up

 At this week's meeting, the CERN Council did what many people expected: effectively ejected Russia and Belarus.  This was done somewhat more softly than had been expected, since, rather than acting immediately, the Council would not extend their cooperation agreements when they expire in 2024.   This was a compromise, since many people had been pushing for faster action.   2024 is far off.   The statement was accompanied by the expected text denouncing the Russian invasion, but it still seems like an attempt to put off any real action.   

It will also not solve the authorship problems faced by the large LHC Collaborations (and likely by smaller groups), where some European funding agencies (most notably the Germans and the Poles - see my previous posts) have told their grantees to stop collaboration with Russian institutions.   And, of course Ukrainian scientists are generally doing this of their own volition.  There may have been some quiet agreement with the European funding agencies, but this will still feel like a slap in the face to the Ukrainian scientists who work at CERN.   As I noted in a previous post, I have enormous sympathy for my Russian colleagues, many of whom expressed their opposition to the war when they could legally do so.  But still, if it comes down to a decision between accommodating scientists from the invaded country or those from the invaders country, my sympathy is clearly with the invaded country.  

On the other hand, scientific ethics require giving appropriate scientific credit to the people who did the work. In large collaborations, this is rule-based - when you join an experiment you have to contribute a certain amount of service work (work to keep the experiment running), take data-collection shifts, etc., and, after a certain amount of time, you are added to the author list for all papers, along with 900-3,000 of your closest colleagues.   For example, the ALICE experiment (at the LHC) experiment rules are available here.  Usually, 6 months or a year after you leave the collaboration, you are removed from the author list.   Neither the general principles of scientific ethics nor these collaboration-based rules contain exceptions for cases when the workers employers behave unacceptably. 

Authorship questions are likely to come up again as the CERN Council decision rattles down to the four LHC experiments, who will need to decide how to handle their author lists.   This will also likely result in a compromise of some sort.  One possibility which I like would be to list the scientists from Russian institutions on the author list, but not list their institutional affiliations. 

Reactions to Ukraine from the world of science

The Russian invasion of Ukraine has now continued for more than two months, and no end is in sight.  Instead of ending the war on May 9th, Putin seems likely to expand it.   'Wait and see' is becoming increasingly untenable.  Two main paradigms drive scientific worlds responses to the invasion:

One paradigm, followed by most of the Western world, is that the Russian invasion is a brutal unprovoked attack that must be punished; we should not associate with the attackers.  Continuing scientific cooperation is 'business as usual,' tantamount to ignoring the invasion.

The second paradigm is that international science is an important way to maintain lines of communication and cooperation.  Maintaining scientific interchange is important for the scientists involved, and keeps the other side from being a nameless, faceless entity.   In the long term, this might influence governments to be less antagonistic toward each other.  

There are of course many slightly more nuanced approaches, mostly focused on punishing the relevant governments and government entities, while protecting the individual Russian and Belarusian scientists to the extent possible.

Both of these approaches have much merit, but they point in different directions.  Different scientists and scientific organizations have emphasized these two paradigms differently.   My personal view is that where they conflict, I will support the invadees over the invaders, and support the Ukrainian point of view, which is clearly that this is not a time for business as usual.  This approach has limits - scientific contact during the cold war clearly had significant benefits for all, but the invasion of Ukraine seems closer to Hitler in 1938 than the cold war.

Germany's Facility for Antiproton and Ion Research (FAIR) has condemned the invasion, and suspended all cooperation with Russian institutions, even at a cost of a several year delay in their new accelerator.    The CALICE Collaboration (a coalition that is developing new methods of calorimetry for high-energy physics experiments) has issued a similar condemnation, suspending Russian institutions from the Institution Board, prohibiting CALICE presentation by scientists from Russian institutions, and also banning CALICE presentations at conferences in Russia.  

Other large projects have taken much less action.  For example, the International Thermonuclear Experimental Reactor (ITER) has not visibly reacted to the invasion.   Similarly, U. S. Dept. of Energy laboratories have not said anything, although some experiments involving both Russian and European collaborators have had intense discussions about the way forward. 

As noted below, CERN has taken a somewhat middle view, issuing a statement of solidarity with Ukraine, suspending much cooperation with Russia, and, although not expelling Russian scientists, stopping new collaboration with Russia.  Further action may be taken at the next CERN Council meeting in June, possibly including expelling Russia.    This would be a major shift for CERN, since it was founded to improve cooperation in Europe in the aftermath of World War II - exactly per the second thrust above.

None of these decisions deal explicitly with scientific authorship for work that is already complete, or largely complete.  Scientific ethics rules require giving authorship credit to the people who did the work.   These rules do not include exceptions for changing rules from funding agencies that require (in the case of Germany, Poland and Finland, at least) an immediate end to collaboration.  

For now,  the large CERN LHC collaborations are posting their papers on the Cornell arXiv, authored by 'the XXX Collaboration', without individual names.  This may buy time, but it is not a long-term solution, since author lists are required before the papers are published in scientific journals.   Some papers from smaller collaborations have come out listing Russian authors, but without their Russian institutional affiliation.   To me, this seems like the least bad solution to a very difficult solution - we properly recognize the work of our Russian colleagues, but avoid giving credit to the institutions that are on record as supporting the war.

 

 

Science in the age of Ukraine: update

 One additional item regarding Russian involvement in world science:  According to a tweet by Robyn Dixon,  the Moscow Bureau Chief of the Washington Post, Russia has now barred university staff from publishing in international (presumably non-Russian) scientific journals or attending international conferences. 

If this is enforced, this will essentially bar all collaborative publications, since I can't imagine non-Russians being willing to publish in Russian journals.  All of the LHC experiments (and many many other international collaborations) have a long pipeline of papers at various stages in the analyzing/writing/editing/publication process.  What will happen to these papers?    

There may be a precedent from the height of the cold war, when the West and the Soviet Union had parallel journal structures, and cross-publishing was uncommon.   A. B. Migda published his' 1956 quantum mechanical calculation of Landau-Pomeranchuk-Migdal suppression of bremsstrahlung and pair production  in both the American Physical Review and the Soviet Doklady Akad Nauk SSR.  Now, the Physical Review article is well known and  still heavily cited, while the Doklady Akad Nauk SSR article is mostly forgotten.  

If all better solutions fall through, one could imagine a solution where the Russian part of a collaboration publishes a result in Russian journals, while the Western part publishes in a Western journal.   I am sure that many readers will be slightly outraged by this idea.  I do not claim that it is a good idea, but it may be the least-bad route forward if the Russian-Western estrangement drags on for longer than different collaboration can hold off on publications in the hope that the author list problem will resolve itself.

Science in the age of Ukraine

 

Watching the news the past two weeks has been difficult – the scenes from Ukraine are reminiscent of World War II, and the brutal unprovoked invasion by Putin’s Russia has few parallels in more recent history.     The one bright spot has been the U. S. and international reaction, where a consensus in support of Ukraine has developed, coupled with an active resupply of weapons and strong sanctions on Russia. 

 

The Russian invasion also affect science.  Science is international, and most large collaborations include Russian and/or Ukrainian colleagues.    Naturally, there has been much talk about if/how to sanction Russian scientists, with many groups favoring their immediate ouster. 

 

Many of these scientific collaborations are long-standing.  The ALICE Collaboration (of which I am a member) at CERN’s [in English: European Organization for Nuclear Research] Large Hadron Collider has roots that go back more than 20 years, and much of the data now being published was taken in the mid 2010’s, with significant Russian involvement in both detector construction, data taking, and calibration and software.   The analysis connected with a single paper typically extends over more than a year, and involves people from multiple institutions.  

 

When a paper is written, there are clear standards for the required level of involvement to merit authorship.   This is true in both the broader scientific world, and, with more specific standards, within ALICE and other large collaborations.   Omitting deserving contributor from the author list can be considered either scientific misconduct (failing to give credit) or plagiarism (if the contributed actually wrote some of the text).   Per these rules, is unethical to rob Russian scientists of scientific credit for the work that they have done.

 

But, people are rightly outraged by Russian behavior. Ukrainian scientists very rightfully do not want to collaborate with Russian scientists, and have called for Russia’s ouster from CERN.  Some European funding agencies have banned collaboration with Russian authors, including joint publications. This extends to scientific journal operations.

 

On the other hand, during the first ~ week of the war, before it became illegal for them, many Russian scientists spoke out against the war. It feels wrong to sanction people who spoke up, at some personal risk.   Now, the scientists have been forced into silence, and their institutions are speaking out in favor of the invasion.   So, one goal would be to sanction the institutes, but not individual scientists.  This is unfortunately easier said than done.

 

Finding the right direction is not easy.  CERN, and most other international organizations) took no action during previous Russian invasions, such as Hungary in 1956, Czechoslovakia in 1968, Afghanistan in 1979 or Crimea and Donbass in 2014. The CERN Council recently decided to suspend Russia’s status as an observer at CERN.  They are not currently ousting the Russian scientists who are already working at CERN, but are also not expanding any ties.  This was clearly an attempt to find a middle ground, and it may be suitable short-term.    Other organizations have taken a range of actions, ranging from nothing (at least so far, such as International Thermonuclear Experimental Reactor (ITER)) to suspending Russian membership (Nuclear Physics European CollaborationCommittee (NuPECC)).  And, many institutions are taking steps to support their Ukrainian colleagues who have been affected by the invasion. 

 

Medium and long term, this solution is not enough, due to some nagging problems. One involves publications.   If Ukrainians and other European scientists will not or cannot (due to funding restrictions) publish with Russians, what do we do with ready-for-submission manuscripts with authors from both groups?   It seems wrong to drop the Russian authors, and at least equally wrong to let the presence of Russian authors keep other scientists from signing these papers.     So, what to do?  One possibility that has been circulating would be to allow the Russian authors to sign the papers, but as individuals, without their Russian institutional affiliations.  Whether that will satisfy everyone remains to be seen. 

 

Disclaimer:  The opinions expressed here are solely my own, and do not represent my employer or any other institutions or collaborations.