Contact Information:golwala at caltech.edu
phone: 626-395-8003
fax: 626-584-9929
Mail Code 367-17
California Institute of Technology
Pasadena, CA 91125
I am a professor of physics in the Division of Physics, Mathematics, and Astronomy at Caltech.
Research Interests:
What is the nature of the dark matter and dark energy that dominate the universe? I am focused on efforts that try to better understand these mysterious components. These efforts tend to have significant technology development aspects: one approach to understanding such elusive phenomena is to find ways to do new and better measurements.
Current Projects (Terribly out of date...):
- Bolocam:
a 144-element millimeter-wave camera for use on the Caltech Submillimeter
Observatory. We use Bolocam to look for
high-redshift dusty galaxies (using the thermal emission
for dust) and galaxy clusters (using the Sunyaev-Zeldovich
effect) and to study well-known galaxy clusters in the SZ
effect. My primary interest is in the measurement of
the abundance of galaxy clusters as a function of
redshift, and correlation of SZ-flux-limited cluster
surveys with optical and X-ray surveys, to better quantify
the contribution and history of dark energy, and
observations of well-known clusters in the SZ to better
understand clusters and the systematics in SZ
measurements.
- Participation in
the Cryogenic Dark
Matter Search II and SuperCDMS experiments,
experiment that uses cryogenic detectors to search for
rare interactions of WIMP dark matter with ordinary
matter. I did my thesis on CDMS I, the shallow-site
pilot experiment.
Want to see what our data look like? See this YouTube realization.
- Development of
Weakly-Interacting Massive Particle (WIMP) dark matter
detectors using Microwave Kinetic Inductance Detectors
(MKIDs) as phonon sensors.
- Development of a multi-band submm/mm-wave camera using MKIDs, MUSIC (MUlticolor Sub/millimeter Inductance Camera). This will succeed Bolocam on the CSO and be a technology demonstrator for the CCAT long-wavelength camera.
- CMB polarization work: involved early on in these projects, but have pulled out due to lack of time. These are very much ongoing experiments. Jamie Bock can serve as graduate advisor. SPIDER, a balloon-borne payload, and BICEP2/Keck Array, a ground-based receiver at the South Pole: experiments to search for the signature of inflationary gravity waves in the cosmic microwave background.
- Development of
the SZ science case for and long-wavelength camera for the
Cornell-Caltech Atacama
Telescope, at 25-m submm and mm-wave telescope to be
sited in the Atacama Desert, currently in the partnership
development stage.
- Engineering work towards a ton-scale WIMP-search experiment using the CDMS technology, the Germanium Observatory for Dark Matter (GEODM). See the talks below for details.
Grad students are welcome to contact me to discuss any of these projects and whether they might provide good thesis topics.
Undergrads: I only take on Caltech students for summer projects or academic year work. I may not be able to respond immediately to your requests.
More information
Here are some recent talks, notes, papers, etc. to provide some more information on these projects.
- Lay
audience talk on dark matter and dark energy (Caltech
Seminar day, 2005): PDF.
- Bolocam
- SZ
anisotropy
survey paper (Ap J 2009)
- Jack Sayers PhD thesis (Dec 2007) on SZ anisotropy survey, including many additional analysis details:
- Instrument description
- Noise performance
- Sky noise studies
- Beam measurements, pointing reconstruction, flux calibration
- Mapmaking and SZ anisotropy constraint technique
- AzTEC (Bolocam II) instrument paper
- Sky noise subtraction paper (Ap J 2010).
- Pointed
cluster
study demonstration paper (5 clusters, Ap J
2011). A longer paper on a sample of 45 clusters
is in prep (Czakon et al).
- Talk on SZ survey results: PDF
- More general talk on cluster astrophysics: PDF.
- SZ
anisotropy
survey paper (Ap J 2009)
- MKID Camera
- LTD12 paper on DemoCam prototype
- LTD13 paper on MKID camera.
- See also the SPIE
2010
proceedings for a number of papers.
- Talk at FNAL on MKIDs for cosmology, including applications for MKID Camera and CMB polarization: PDF.
- SPIE
2012 paper.
- See also above Bolocam talks
- CCAT (see the CCAT page for the full feasibility study report):
- SZ science:
- Section of the CCAT feasibility study report (Jan, 2006) on SZ science: PDF.
- An
earlier,
more detailed version: PDF.
- Technical note describing calculations for above document: PDF.
- AAS Jan 2008 poster on above: PDF.
- AAS Jan 2013 poster on LWCam design and science (available from this page).
- AAS
Jan 2013 talk
on CCAT cosmology/cluster science by Rachel Bean
(available from this
page).
- Instrumentation
- Dark Matter
- CDMS 2008 results and MKID-based dark matter detector: PDF.
- CDMS 2008 results paper
- LTD12 paper on MKID-based WIMP dark matter detector design, LTD12 paper on MKID-based X-ray test devices.
- LTD13 paper on MKID-based X-ray test devices and injector devices.
- Talk on current status and future of CDMS/SuperCDMS/GEODM (Sep 2009): PDF.
- Review talk on dark matter searches (Aug 2009): PDF.
- Caltech PRC "Road to Zeptobarn Dark Matter" on current status of CDMS/SuperCDMS/GEODM, other direct detection searches (Feb 2010): PDF (24 MB!).
- Seminar
talk on 2009/12 new results from CDMS II: PDF. Paper in Science.
- Talk at FNAL on MKIDs for cosmology, including applications for dark matter detection: PDF.
- CDMS low-mass results paper and Dave Moore's thesis on these low-mass results and MKID-based dark matter detector.
- CDMS
low-mass annual modulation search paper.
- Assorted
Teaching
Physics 106ab, classical mechanics. (2004-05, 2005-06, 2006-07)
Physics 106bc, electricity and magnetism (2012-2018).
Physics 125ab, quantum mechanics. (2007-2008, 2008-2009)
Physics 135c, experimental non-accelerator particle physics (2007)
This page last updated 2018/03/22.