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Post summary – April 2009 May 1, 2009

Posted by dorigo in astronomy, Blogroll, cosmology, internet, news, personal, physics, science, social life.
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As the less distracted among you have already figured out, I have permanently moved my blogging activities to www.scientificblogging.com. The reasons for the move are explained here.

Since I know that this site continues to be visited -because the 1450 posts it contains draw traffic regardless of the inactivity- I am providing here monthly updates of the pieces I write in my new blog here. Below is a list of posts published last month at the new site.

The Large Hadron Collider is Back Together – announcing the replacement of the last LHC magnets

Hera’s Intriguing Top Candidates – a discussion of a recent search for FCNC single top production in ep collisions

Source Code for the Greedy Bump Bias – a do-it-yourself guide to study the bias of bump fitting

Bump Hunting II: the Greedy Bump Bias – the second part of the post about bump hunting, and a discussion of a nagging bias in bump fitting

Rita Levi Montalcini: 100 Years and Still Going Strong – a tribute to Rita Levi Montalcini, Nobel prize for medicine

The Subtle Art of Bump Hunting – Part I – a discussion of some subtleties in the search for new particle signals

Save Children Burnt by Caustic Soda! – an invitation to donate to Emergency!

Gates Foundation to Chat with Bloggers About World Malaria Day – announcing a teleconference with bloggers

Dark Matter: a Critical Assessment of Recent Cosmic Ray Signals – a summary of Marco Cirelli’s illuminating talk at NeuTel 2009

A Fascinating New Higgs Boson Search by the DZERO Experiment – a discussion on a search for tth events recently published by the Tevatron experiment

A Banner Worth a Thousand Words – a comment on my new banner

Confirmed for WCSJ 2009 – my first post on the new site

Think like an experimental particle physicist – second (and last) part February 27, 2009

Posted by dorigo in games, humor, physics, science.
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While putting together the scores to evaluate the answers to the 11 questions of the previous post, I realized that they are not enough for a fair classification. So here are a few more quizzes for those of you who found my effort worth paying back with five more minutes of your time.

  • K) You are found in the library of your Department. Why was that ?
  1. Why, I had an hour to kill…
  2. I am just checking out the new librarian (he/she’s cute).
  3. They told me there are coupons to cut away for free radioactive samples on this month’s issue of Physics Today.
  4. They threatened to expel me if I did not bring back the overdue copy of DH. Perkins’ book.
  • L) How much is 87 times 945 ?
  1. About 80 thousand.
  2. About 82 thousand.
  3. I left my pocket calculator in the office upstairs.
  4. (after a minute)  82,215  (ignore my fast breathing).
  5. 82 215 (mind the space -I take pride in following AIP style rules!).
  6. More or less 10^5.
  • M) The mean-looking airport cop finds an electronic board wrapped in a sweater in your carry-on.
  1. You go back to the check-in counter: you came early on purpose.
  2. You try to explain it is innocuous HEP hardware.
  3. You manage to power it up by fiddling with the laptop power cord to show the two-digit LCD mounted on it does come alive.
  4. You start arguing that the sign with red crosses on lighters, firearms and batteries mentions nothing even vaguely resembling a CAMAC module.
  5. You let them dump it, too bad for science -and whoever uses CAMAC nowadays, after all.
  • N) Your paper draft receives really nasty comments from your collaborators
  1. You write down the names of the bad guys on your small red booklet in the bottom drawer – their time in front of the muzzle will come one day!
  2. You answer in kinds on a rage, with carbon-copy to the spokespersons, making a fool of yourself.
  3. You answer as politely as you can in a very detailed manner, cursing yourself softly while you feel like you’ve bent over.
  4. You decide the paper really is not worth that much and forget about it for a month or two.
  • O) After your presentation is over,  the session convener asks a tough question and you do not even know what he or she is talking about.
  1. You say you do not know the answer and display your best smile, hiding the sweating.
  2. You repeatedly pretend you did not understand the sentence until he or she decides it’s time to move on.
  3. You think it wasn’t such a good idea to grab that last-minute chance for a plenary talk.
  4. You go to a random back-up slide and discuss it in detail for five minutes, trying to look meaningful.
  • P) A science reporter calls and asks you information on the  hunt for supersymmetry.
  1. You feel flattered, get carried away, and end up disclosing reserved information from your experiment.
  2. You direct him or her to the experiment spokespersons.
  3. You pretend you’re the switchboard operator.
  4. You ask what magazine is that for, and after hearing it’s “New Scientist” you hang up.
  • Q) They sent you a paper to be reviewed. It sucks big time.
  1. Feeling true to your duties, you implacably point out each and every imperfection with rigor and an occasional bit of sadism.
  2. You reckon nobody’s going to read the paper anyway, so you send back two lines saying the paper looks ok but would they please use AIP style rules ?
  3. You are fought between your duties and your compassion for the poor post-doc who did most of the work  to get the paper to your desk, and try to balance the two things, ending up screwing both -the author feels raped and the paper does not get any better from your review.
  4. You would never accept to get into an editorial board, it’s just such a waste of research time.
  • R) You are on owl shift and your colleagues are out of the room for coffee and cookies, when every screen turns red, alarms sound, and an ominous-looking warning sign start flashing on the silicon cooling contol panel.
  1. You run to the silicon crash button and press it.
  2. You silence all alarms and fetch the emergency procedures folder, then start reading it
  3. You rush to call your colleagues.
  4. You sneak out, join your colleagues and serve yourself a coffee, then look over the glass door and mention there appears to be  something flashing inside as if you just noticed it.
  • S) You feel you think like an experimental particle physicist because…
  1. You do not work in HEP, but at least one answer in each of the 19 questions above made a lot of sense to you
  2. You read this blog and you think it really does not take much to be a HEP physicist.
  3. You are a theorist and although you have trouble with practicalities you think experimentalists have similar thinking processes.
  4. You are a scientist from another field and you know how to tie your shoes.
  5. You are a scientist from another field and you wear sandals.
  6. You are sure you do not think like an experimental particle physicist in the least.

Data preservation survey October 30, 2008

Posted by dorigo in internet, physics, science.
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Today I found twenty free minutes to fill out a questionnaire about data preservation in the CERN web site.

I have always considered the issue of data archiving very important, even crucial for the advancement of Science. I find it appalling that huge moneys are invested in building and operating large particle physics experiments, with no clear plan about what to do with the data, once the experiments close down.

There are several reasons why one needs to ensure that data is preserved.

  1. First and foremost, we do not burn books. Why should we dispose of data files we took so much care, years of efforts and the work of thousands of people, to put together ?
  2. Old data is potentially crucial to confirm new results, to disprove others, to compare to them. I hope I can give a very clear example of what I mean, this evening, when I will discuss a new result by CDF which is potentially groundbreaking, and which might be tested with older data from CDF itself as well as other hadron collider experiments.
  3. Old data may be invaluable as a laboratory to train new scientists. The number of Ph.D. students working on LHC experiments who have never ever worked with real data is disturbing: can we train them on Monte Carlo simulations ? Sure, but it is not the same thing, not really.
  4. The data is ultimately a world heritage. I maintain that it is not the property of this or that collaboration. The people lucky enough to have been given the privilege of analyzing data from high-energy physics experiments have done so thanks to the funds provided by whole countries. The data -being a form of distilled knowledge- are owned by the peoples, and I am sorry if I sound like a communist here. If you do not agree, it is you who look like a fool to me.

So, if you have a wish to provide your input in this important issue, why don’t you take the time to visit the site http://cern.ch/data-preservation-survey ?

Where the heart beats October 16, 2008

Posted by dorigo in personal, physics, science.
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The picture above made the headlines today in repubblica.it, one of the news sites I read most often. It shows a little mouse, originally intended as a meal supplied to a viper, managing to invert the food chain, killing the monster. I am stating the obvious when I say we usually rejoice when we see something like that happening: we always root for the weak against the strong, especially if we feel weak ourselves -and don’t we all, in some respect ?

The picture had me thinking about the competition between the Tevatron and LHC particle accelerators. Since the LHC has not produced a single proton-proton collision in the core of the CMS and Atlas detectors yet, while the Tevatron has supplied CDF and D0 with an enormous amount of collisions which are fruiting scores of groundbreaking physical results, the two machines might be argued to not be competing yet. But that would be a myopic assessment, on several levels.

  • There is competition for the funding of experiments. Lab directors, experiment heads, and faculty members are very sensitive to this issue of course, since it affects their chances of leadership and power. Funds to particle physics experiments are getting cut these days, and the many experiments have to fight against each other to keep their budget plans intact. The LHC has been competing for funding with the rest of the HEP facilities since the start of its construction, or arguably even before then.
  • Then there is of course the fight for a place under the media spotlights. It is a level of competition tightly connected with the funding one, but it has some additional branches, since the media attention can be an important fuel to boost the career of scientists. The recent media hype for the startup of LHC on September 10 was a masterful organization by CERN general director Aymar, and the following incident with the magnets in sector 34 was troublesome to CERN as much for its media impact as it was for the lab schedule. Of course, at the Tevatron and elsewhere many met the global interest for LHC in the former occasion with ill-concealed jealousy, and the latter with more evident satisfaction.
  • A third level of competition, in turn somewhat connected to the second, has its ground on the scientific conferences around the world which are now scheduled every second week. Presenting scientific results at conferences is a very important item in the construction of a strong curriculum, and some talks increase the prestige of the speakers. The Tevatron has had a large share of talks allotted at all the major conferences in the recent past, due to the mass of new results it produced; but Atlas and CMS have started being allotted several talks already, which will be used to discuss “Monte Carlo analyses” rather than results on real data. Still, this causes a compression of the benefits of the Fermilab scientists.
  • And then there is the fight for the Higgs. The Tevatron experiments are still caressing hopes to find the Higgs boson before LHC does, and are thus squeezing their brains to improve the already excellent analyses they have been producing. This year, for the first time, a direct limit on the Higgs boson mass has been set by CDF and D0 in a joint effort. Although the limit is not stringent yet (a single mass value has been excluded, 170 GeV), the two experiments are working to wipe off the board the whole high-mass region, where the LHC would have no trouble in finding a significant signal with one year worth of data. If the Higgs is proven to be lighter than 130 GeV or so, the fight between the two sides of the Atlantic is promised to become red-hot in the next two-three years, depending on whether the Tevatron gets funded to run for the fiscal year 2010.
  • Finally, there might be new physics out there, and it might still be at reach of the Tevatron. The six-months delay of the LHC data taking is making this race even more interesting, especially since CDF and D0 are reaching a level of sensitivity in the SUSY parameter space that might enable them to discover new physics before LHC.

So, as you see, there is competition in HEP between LHC and the Tevatron even if the former has not begun taking data yet. The mouse of the picture above, in my mind, is the Tevatron biting the LHC’s throat, turning the tables when everybody expects the latter to entertain itself with a quiet meal. This is still possible. If CDF or D0 discovered SUSY, such an event would be a defeat of incredible proportions for CERN, echoing the disasters of the sixties and the seventies, when the US were banqueting lavishly with new discoveries, barely leaving bread crumbs for Europe.

And where do you stand“, you might well ask, since I am working for both CMS at CERN and CDF at the Tevatron ? Well, I am slightly embarassed to answer, but I must say that until CDF closes down, my heart beats for it. The first love is the one you never forget, and to that piece of rethorics today I can add the image of the little mouse. Curious feeling: I am spending 80% of my research time doing my best to help make CMS a success, but I still caress some hope that it will, at least to some extent, fail to the hands of my former love. If you think that is despicable, please consider: what is important is not who gets a Nobel prize here. It is a win-win situation for whom, like me and most of you, only cares for the advancement of science. CMS, Atlas, CDF, D0: who cares ? All I care is to find out the truth!