Last bits on the HAWC review

Am back from the site and from the Puebla Review of the HAWC experiment. There is some online information showing the schedule and documentation details of the review here at this location. The Photo Gallery is especially good.

Science and technical reviews

So, this is probably going to be a dull entry, but I wanted to detail what sort of event I'm attending this week down in Puebla. This is a review called by the funding agencies to assess the progress of the experiment and verify that the money is being spent well.

To do that, there are management folks from the National Science Foundation and the Department of Energy (the main US funders of the project), some science reviewers from similar (or not especially similar) projects acting as peer reviewers, and folks from the Mexican funding agencies (which have a complicated setup that I don't fully understand) here to listen to talks from all different pieces of the experiment and ask questions.

Physicists are generally, let's go ahead and stereotype a little bit, pretty critical, and willing to push on questions for which they are unable with the answers. So a Q&A with a panel of physicists can be a loud, even brutal business. Obviously the management folks are much more reserved in such questioning. So talks have to be vetted ahead of time and delivered with some care.

So far the review has been going well, the project is in relatively good shape. Some things, especially for the site construction work, have been moving slowly, but delays are of a few months, nothing too horrible. The project now has about 135 people in the US and Mexico, and the total budget for the project will be on the order of $15M.

HAWC Observatory

You can get more information from the new website.

A few nature photos from my last visit to the HAWC site

Minor detour from the South Pole

This week I'm headed to Puebla, Mexico for the joint NSF-DoE (National Science Foundation and Department of Energy, the two main US funding sources for science that isn't related to your congressman's liver (that would be the National Institutes of Health, funding whatever the congressfolks are scared of medically)) review of the HAWC experiment. This is a science and management review to make sure that we're spending the taxpayer money well, and that the project is progressing reasonably.

HAWC is the High Altitude Water Cherenkov experiment. That means it's being built at high altitude, 4100 meters or about 14000 feet above sea level, in order to get higher up into the cascade (or shower) of energetic particles produced when cosmic rays or gamma rays hit the top of the atmosphere. The detector technology is Water Cherenkov, that is, we observe the light emitted from fast-moving particles traversing through a water tank. The light is detected with photomultiplier tubes (PMTs) capable of seeing single photons with nanosecond (billionth of a second) resolution. It's the gamma rays at energies at the top of the atmosphere of near 1 TeV (10^12 electron volts) that are of particular interest.

One of the main goals of HAWC is to observe the whole sky (rather than like an optical telescope, just the small patch of the sky one is aimed at) in these TeV gamma rays (which are super-high energy photons) for transient sources. The main goal is to observe gamma ray bursts (GRBs, very energetic astronomical explosions much of the way across the universe) at higher energies than previously seen. This would enable us to better understand the physics of the GRB sources and the propagation (travel) of the photons from those sources to the Earth.

To one specific high altitude valley in Mexico to be precise. It's a beautiful site, so look for photos in the next couple of days...