The Particle Cosmology group at the University of Illinois explores the connections betwen the universe's workings on its largest and smallest scales. We develop and employ “readout systems” for the cosmic laboratory: instruments to help tease out the signatures of new fundamental physics from astrophysical messengers. Recent efforts have focused on measurements of the cosmic microwave background (CMB), the afterglow of the hot early universe.

Our group’s research touches upon a broad range of topics bridging the domains of cosmology and fundamental physics. Our instrumentation employs cutting-edge technologies developed in condensed matter and engineering labs, including superconducting detectors and millimeter-wave optics. Our data analysis efforts involve large-scale computing and simulations. Students develop a wide variety of skills in a collaborative environment while addressing some of the highest-profile questions of modern cosmology.

Research Activities


SPIDER is an ambitious balloon-borne instrument seeking evidence of primordial gravitational waves in the polarization of the Cosmic Microwave Background (CMB). SPIDER completed a 16-day long-duration balloon flight over the Antarctic ice in January 2015 (launch video), mapping ~12% of the sky at 95 and 150 GHz. The data are under analysis, and development is underway toward a second flight (Dec. 2018).

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The BICEP program employs compact refracting telescopes to make the deepest (lowest-noise) maps to date of CMB polarization on degree angular scales. BICEP2 observed from the South Pole for three years, culminating in a 2014 detection of B-mode polarization (since ascribed to galactic dust emission). The Keck Array, BICEP3 (shown), and the upcoming BICEP Array continue this program with ever-more-sensitive instruments observing at multiple frequencies.

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There is now abundant evidence that the bulk of the universe's matter is in some dark form, not found the Standard Model of particle physics. The Cryogenic Dark Matter Search seeks to detect the interactions of particle dark matter in terrestrial detectors, which are operated at millikelvin temperatures in an ultra-low-radioactivity environment deep underground.

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The CMB community is engaged in planning and R&D toward a coordinated ground-based observational program, known as "CMB - Stage IV". S4 will bring to bear data from multiple telescopes and observing sites to probe qualitatively new parameter space for fundamental physics and astrophysics.

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PICO (Inflation Probe)

PICO is a concept for a satellite mission to probe the millimeter-wave sky at post-Planck sensitivities. Our group is engaged with a NASA-funded community mission study and related technology development efforts.

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TIM is a funded long-duration balloon mission to study the history of cosmic star formation through intensity mapping at THz frequencies. The payload's KID spectrometer will be a technology pathfinder for Origins Space Telecope.

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Our Team

Jeffrey Filippini

Assistant Professor of Physics and Astronomy
Ph.D. Berkeley, 2008
405 Loomis Lab

Department Homepage

CV . Publications . Antarctica Blog

Ben Osherson

Physics Ph.D. Student
A.B. Physics 2014, Princeton

Elle Shaw

Physics Ph.D. Student
B.A. Physics 2016, Greenville College

Rong Nie

Physics Ph.D. Student
B.N.S. Applied Physics 2015, Univ. of Sci. and Tech. of China
M.S. Physics 2016, U. Chicago

Amber Lennox

Physics Ph.D. Student
M.Sci. Theoretical Physics 2016, Univ. of Glasgow

Carina Baker

Physics Ph.D. Student
B.A. Physics 2017, Univ. of Chicago

Ahmed Imran

Class of 2021

Alumni and Visitors

Jianyang Fu

B.S. Physics 2018, UIUC
Ph.D. student, UIUC Astronomy

Derek Glennon

B.S. Physics 2018, UIUC
Scientific Games Corp.

Robert Gramillano

B.S. Physics/Astro 2016, UIUC

Riccardo Gualtieri

Postdoc 2015-20
Argonne National Laboratory

Bryan Hendricks

REU 2017
B.S. 2019, Illinois Institute of Technology
Ph.D. student, Penn State Physics

Harshil Kamdar

B.S. Phys/Astro 2016, UIUC
Ph.D. student, Harvard Astronomy

Cyrus Liu

Class of 2020

Hannah Messenger

REU 2018
B.S. 2020, Case Western

Alex Navarre

B.S. Physics 2018, UIUC
Ph.D. student, U. Cincinnati Physics

Kaliroë Pappas

B.S. Physics 2018, UIUC
Ph.D. student, MIT Physics

Charmi Patel

Class of 2020

Aaron Smothers

B.S. Astro 2019, UIUC

Lunan Sun

B.S. Physics 2015, UIUC
Ph.D. student, UIUC Physics

Emma Western

REU 2016
B.S. 2018, University of St. Thomas
Ph.D. student, LSU

Hilary Utaegbulam

REU 2019
B.S. 2020, University of Houston

Recent News

  • Feb. 16, 2020: Ben's LTD paper on the particle response of antenna-coupled TES arrays has been accepted to appear in JLTP, and been posted on the arXiv! Several other LTD papers for BICEP Array have also been accepted and posted.

  • Dec. 16-19 2019: Prof. Filippini presented a talk on SPIDER and a poster on cosmic ray response at B-Mode from Space 2019 in Garching, Germany.
  • Oct. 2-4, 2019: U. of Illinois hosted the inaugural meeting of the South Pole Observatory (SPO) collaboration, a joint effort between the BICEP/Keck and SPT collaborations to build the future of CMB research at the South Pole.
  • Jul. 22-26 2019: Ben presented a talk at Low-Temperature Detectors 2019 in Milan, Italy. Riccardo and Prof. Filippini also attended.
  • Apr. 19, 2019: Best wishes to our undergrad alums heading off to pursue Ph.D.s! In the fall Bryan will be attending Penn State, and Kaliroë will attend MIT.
  • Feb. 28, 2019: The mission study report for PICO, a concept for a probe-class CMB satellite, has been submitted to NASA and posted to the arXiv.

  • Dec. 20, 2018: Kick-off meeting at the University of Arizona for our newly-funded balloon project, TIM (STARFIRE)!
  • May 29, 2018: Welcome to our 2018 REU student: Hannah Messenger, from CWRU.
  • May 13, 2018: Congratulations to our class of 2018 graduates: Frank Fu, Derek Glennon, and Alex Navarre!
    Prof. Filippini was the faculty speaker at the 2018 Physics/Astronomy Convocation ceremony.
  • May 1-3, 2018: Ben presented a poster on the cosmic ray response of TES arrays at the PICO (CMB probe) meeting.
  • Apr. 4, 2018: Elle is a 2018 recipient of the Physics department's Scott Anderson Outstanding Graduate Assistant Award!
  • Mar. 7, 2018: The last two SPIDER 280 GHz telescopes have shipped from UIUC to Princeton, where they will be integrated with the flight payload.
  • Feb. 14, 2018: Prof. Filippini delivered the Physics Colloquium: "A View of the Dawn of Time from Above the Clouds".

  • Dec. 15, 2017: Prof. Filippini has been named a Fellow of the U of I Center for Advanced Study for the 2018-19 academic year.
  • Oct. 24, 2017: For Dark Matter Day at U of I, Prof. Filippini and colleagues hosted a screening of Seeing the Beginning of Time, followed by a panel discussion. About 150 people attended!
  • Sep. 28, 2017: Our test cryostat is sub-Kelvin once again! We'll be characterizing the response of CMB detectors to particle radiation using Ben's "monotile" test jig.
  • Sep. 22, 2017: Prof. Filippini was one of three hosts of Astronomy on Tap at Pygmalion 2017.
  • Aug. 2, 2017: SPIDER's first scientific result from the 2015 flight has been published in the Astrophysical Journal: a new upper limit on the circular polarization of the CMB.
  • Jul. 17-21, 2017: Prof. Filippini and Dr. Gualtieri traveled to Kurume, Japan for Low-Temperature Detectors 2017, where they presented a poster on SPIDER and studies of cosmic ray response in CMB detectors.
  • Mar. 23, 2017: Prof. Filippini gave an invited review talk on CMB observations at an Aspen Winter Conference: "From the LHC to Dark Matter and Beyond".

  • Nov. 5, 2016: Professor Filippini delivered a public lecture, The Hidden Universe: Dark Matter and Dark Energy, as part of the Saturday Physics for Everyone series.
  • Nov. 1, 2016: The SPIDER project has been renewed for a second flight in 2018! SPIDER is funded by NASA and by the Canadian Space Agency.
  • Jun. 16, 2016: Professor Filippini hosted Astronomy on Tap Champaign-Urbana, giving a talk about dark matter at Pizza M.
  • Feb. 2, 2016: The SPIDER test cryostat has arrived at U of I in preparation for SPIDER-2 receiver work.
  • Jan. 20, 2016: The BICEP2/Keck 95+150 GHz paper has been published as an Editor's Choice in Physical Review Letters.

  • Nov. 22, 2015: This Thanksgiving we give thanks that SPIDER has begun her long trip back to the States, thanks to heroic recovery efforts in Antarctica this week by Ed Young (Princeton Ph.D. student) and the British Antarctic Survey!
  • Oct. 30, 2015: New results from Keck Array (95+150 GHz) and BICEP2 (150 GHz) set the most stringent limits to date on primordial gravitational waves. This is the first polarization-only constraint that surpasses that from the CMB temperature anisotropies: arXiv:1510.09217.
  • Aug. 14, 2015: Our group has been awarded its first external research funding: a NASA Strategic Astrophysics Technology grant, in collaboration with Caltech/JPL!
  • Mar. 9, 2015: The BICEP2/Keck Array/Planck joint analysis has been published as an Editor's Choice in Physical Review Letters.
  • Feb. 4, 2015: SPIDER's data disks have been recovered from the ice by members of the British Antarctic Survey! Data analysis will shortly begin in earnest.
  • Jan. 1-18, 2015: SPIDER has completed its first science flight over Antarctica! See story in Caltech News.

Selected Publications


R. Gualtieri, J.P. Filippini et al., "SPIDER: CMB polarimetry from the edge of space", arXiv:1711.04169 (to appear in JLTP 2018)

J.M. Nagy et al., "A New Limit on CMB Circular Polarization from SPIDER", ApJ 844, 151 (2017)

J.E. Gudmundsson et al., "The thermal design, characterization, and performance of the Spider long-duration balloon cryostat", Cryogenics 72, 65 (2015)

A.S. Rahlin et al., "Pre-flight integration and characterization of the SPIDER balloon-borne telescope", Proc. SPIE 9153 (2014)

A.A. Fraisse et al., "SPIDER: probing the early universe with a suborbital polarimeter", JCAP 04, 047 (2013)

D.T. O'Dea et al., "Spider optimization II: Optical, Magnetic and Foreground Effects", ApJ 738, 63 (2011)


P.A.R. Ade et al., "Constraints on Primordial Gravitational Waves using Planck, WMAP, and New BICEP2/Keck Observations through the 2015 Season", Phys. Rev. Lett. 121, 221301 (2018)

P.A.R. Ade et al., "New bounds on anisotropies of CMB polarization rotation and implications for axion-like particles and primordial magnetic fields", Phys. Rev. D 96, 102003 (2017)

P.A.R. Ade et al., "Measurement of Gravitational Lensing from Large-Scale B-Mode Polarization", ApJ 833, 228 (2016)

P.A.R. Ade et al., "Improved Constraints on Cosmology and Foregrounds from BICEP2 and Keck Array Cosmic Microwave Background Data with Inclusion of 95 GHz Band", PRL 116, 031302 (2016)

P.A.R. Ade et al., "Measurements of B-mode Polarization at Degree Angular Scales and 150 GHz by the Keck Array", ApJ 811, 126 (2015)

P.A.R. Ade et al., "A Joint Analysis of BICEP2/Keck Array and Planck Data", Phys. Rev. Lett. 114, 101301 (2015)

P.A.R. Ade et al., "Detection of B-mode Polarization at Degree Angular Scales by BICEP2 ", Phys. Rev. Lett. 112, 241101 (2014)

Technology Development

B. Osherson et al., "Particle response of antenna-coupled TES arrays: results from SPIDER and the lab", arXiv:2002.05771 (accepted to appear in JLTP 2020)

A.S. Bergman et al., "280 GHz Focal Plane Unit Design and Characterization for the SPIDER-2 Suborbital Polarimeter", arXiv:1711.04169, J. Low Temp. Phys. 193, 1075 (2018)

P.A.R. Ade et al., "Antenna-coupled TES bolometers used in BICEP2, Keck Array, and SPIDER", Astrophys. J. 812, 176 (2015)


R. Agnese et al., "Silicon detector results from the first five-tower run of CDMS II", Phys. Rev. D88, 031104(R) (2013)

Z. Ahmed et al., "Dark matter search results from the CDMS II experiment", Science 327, 1619 (2010)

Z. Ahmed et al., "Search for Weakly Interacting Massive Particles with the First Five-Tower Data from the Cryogenic Dark Matter Search at the Soudan Underground Laboratory", Phys. Rev. Lett. 102, 011301 (2009)

Media and Outreach

Professor Filippini is an organizer of Astronomy on Tap Champaign-Urbana, and has presented in June 2016 and at Pygmalion 2017.

Professor Filippini is a contributor to "Whys Guy Wednesdays", part of the Morning Show on WCIA3 TV, Wednesday mornings at 9:30.

Our lab members have been featured in...

An educational video for Dark Matter Day by the U of I Physics department (Oct. 2017)

Saturday Physics for Everyone - "The Hidden Universe: Dark Matter and Dark Energy" (Nov. 2016) (YouTube)

The Big Picture Science radio show and podcast (Jan. 2015)

Scientific American (Nov. 2014)


Contact Us

Our lab is part of the Department of Physics in the The Grainger College of Engineering at the University of Illinois at Urbana-Champaign.

Prof. Filippini: 405 Loomis Lab
Group office: 494 Loomis Lab
Laboratories: 179 & 497 Loomis Lab

Shipping address: MRL Shipping and Receiving, 104 S. Goodwin Ave., Room 190N, Urbana, IL 61801

Contact Professor Filippini (jpf@illinois.edu) if you're interested in joining our team.