TACOS 2026

22 Oct 2026, 18:00 → 24 Oct 2026, 20:30 America/Chicago

Kimberly Boddy (University of Texas at Austin), James Dent, Andrew Long (Rice University), Joel Meyers (Southern Methodist University), Kevin Kelly (Texas A&M University), Kevin Huffenberger (TAMU)

Theoretical Astroparticle and Cosmology Symposium in Texas

This meeting brings together researchers interested in topics at the intersection of theoretical particle physics, astrophysics, and cosmology. Participants from various institutions in Texas present and discuss the latest developments in their subfields, with the aim of fostering ideas and collaborations among faculty, postdocs, and graduate students. The host institution rotates from year to year to enable interactions with local experts in neighboring subfields.

Main meeting website: https://sites.google.com/view/texas-tacos/home

Scientific Organizing Committee:

Kimberly Boddy (UT Austin)
James Dent (Sam Houston)
Kevin Huffenberger (Texas A&M University)
Kevin Kelly (Texas A&M University)
Andrew Long (Rice)
Joel Meyers (SMU)

Thursday 22 October

Hagler Institute Nobel Lecture

1 The Universe From Beginning to End

Dr. Brian Schmidt, renowned astrophysicist and Nobel Prize winner, will present on his team’s discovery that the expansion of our universe is accelerating, a finding that changed our understanding of the universe by showing that about 70 percent of the universe’s mass is “dark energy.”

Dr. Brian Schmidt is an American Australian astrophysicist at the Australian National University’s Mount Stromlo Observatory and Research School of Astronomy and Astrophysics. In 2011, Schmidt and his team were awarded the Nobel Prize in Physics with their discovery that the expansion of our universe is accelerating. This scientific finding changed our understanding of the universe by showing that about 70 percent of the universe’s mass is in a previously unknown form, now usually referred to as “dark energy.”

Reception immediately following the lecture

This program is free and open to the public. Organized independently from TACOS.

Special location: Annenberg Presidential Conference Center

Registration is requested.

Speaker: Brian Schmidt (Australian National University)

Location

Registration link

Friday 23 October

Friday Morning

Convener: Kevin Kelly (Texas A&M University)

2 Welcome & Introduction

Speaker: Kevin Kelly (Texas A&M University)

3 TBD -- Steve Finkelstein

4 TBD -- Junehyoung Jeon

5 Talkitos

10:40 Coffee Break

Friday Morning: Friday Morning 2

Convener: Joel Meyers (Southern Methodist University)

6 Talkitos

7 TBD -- John Chisholm

8 TBD -- Alessandra Venditti

9 Talkitos

10 Group Photo

12:30 Lunch

Friday Afternoon: Friday Afternoon 1

Convener: Kimberly Boddy (University of Texas at Austin)

11 Talkitos

12 Search for Dark Matter in an Extended Nuclear Recoil Energy Window with LUX-ZEPLIN -- Dan Hunt

LUX-ZEPLIN (LZ) is a 7-tonne dual-phase xenon time projection chamber, located at the Sanford Underground Research Facility in Lead, South Dakota. While LZ typically searches for low-energy nuclear recoils indicative of a spin-independent WIMP, an extended nuclear recoil energy window up to ~270 keV enables searches for alternative models of dark matter, where low-energy recoils are suppressed. Recent analysis of 2.84 tonne-years of data resulted in the observation of one event consistent with a ~248 keV nuclear recoil, in tension with the background-only hypothesis at a global significance of 2.6σ. This talk presents an experimental overview of the extended-window analysis, including background modelling, rare background topologies, and prospects for a definitive explanation of this event of interest.

Speaker: Dan Hunt (University of Texas at Austin)

13 TBD -- Debopam Goswami

Speaker: Debopam Goswami (Department of Physics & Astronomy, Texas A&M University)

14 TBD -- Jenna Samuel

15 Talkitos

15:30 Coffee Break

Friday Afternoon: Friday Afternoon 2

Convener: Andrew Long (Rice University)

16 Talkitos

17 TBD -- Cristian Vargas

18 TBD -- Claudia Ratti

Speaker: Claudia Ratti

19 Probing Strong-Field Physics in X-ray Emission from Magnetized Neutron Stars

During the last five years, the Imaging X-ray Polarimetry Explorer (IXPE) has provided intensity and polarization information on the soft X-ray signals from the surfaces of seven magnetars. This multi-faceted dataset bolsters the ability to probe magnetar geometry and physics with new levels of insight. In support of these advances, we have developed and enhanced a sophisticated Monte Carlo simulation of radiative transport in highly-magnetized neutron star atmospheres. The code, named MAGTHOMSCATT, includes treatment of general relativistic light propagation and the influences of QED vacuum birefringence in the magnetosphere. Probes of geometry are presented for the radio magnetar 1E 1547-5408, indicating that both the magnetic axis and the viewer direction are close to being aligned with the rotation axis. In this talk, I will discuss how combined radio and IXPE X-ray polarization data for this magnetar provides strong evidence for the action of vacuum birefringence in its magnetosphere, advancing the case for a sought-after proof of this fundamental QED physics effect.

Speaker: Hoa Dinh (Rice University)

20 Talkitos

18:00 Dinner

Saturday 24 October

Saturday Morning

Convener: Kevin Huffenberger (Texas A&M University)

21 Maping the nanohertz gravitational sky

Pulsar timing arrays (PTAs) have announced evidence for the presence of a nanohertz gravitational wave background (GWB). However, we do not yet know the source of this GWB. In this talk, after a brief introduction to PTAs, I will describe how spatial mapping of the GWB can provide information beyond that available from just its spectrum. I will also introduce some new methods and insights in the search for anisotropy. I will end with a brief discussion on how anisotropy in combination with the spectrum of the GWB may allow us to disentangle one produced by supermassive black hole binaries from cosmological sources.

Speaker: Prof. Nihan Pol (Texas Tech University)

22 Seeing the Light: Supermassive Black Hole Binaries

Binary supermassive black holes are expected to be common based on models of hierarchical structure formation and observations of galaxy merger rates. Their electromagnetic counterparts, however, are extremely challenging to detect, due mainly to degeneracies with other phenomena. I will discuss the possible observational signatures and existing candidates for supermassive black hole pairs and extreme mass ratio inspirals. I will also describe their potential detectability using existing and planned missions and surveys up to the launch of the LISA mission.

Speaker: Prof. Krista Lynne Smith (Texas A&M University)

23 TBD -- Bai-Chiang Chiang

10:20 Coffee Break

Saturday Morning: Saturday Morning 2

Convener: Louis Strigari (Texas A&M)

24 TBD -- Masoom Singh

Speaker: Masoom Singh (Texas A&M University)

25 TBD -- Alex FIlipenko

26 TBD -- Ben Rose

12:20 Lunch

Saturday Afternoon

Convener: James Dent (Sam Houston State University)

27 TBD -- Radhakrishnan Srinivasan

28 Solar Constraints on Heavy Neutral Leptons with Tau Neutrino Mixing

Speaker: Vedran Brdar (Oklahoma State University (US))

29 TBD -- Nityasa Mishra

Speaker: Nityasa Mishra

30 TBD -- Anil Thapa

Speaker: Anil Thapa (Colorado State University)

31 Closing

Speaker: Kevin Huffenberger (TAMU)