
NSF Org: |
PHY Division Of Physics |
Recipient: |
|
Initial Amendment Date: | September 6, 2018 |
Latest Amendment Date: | September 6, 2018 |
Award Number: | 1820770 |
Award Instrument: | Standard Grant |
Program Manager: |
Keith Dienes
kdienes@nsf.gov (703)292-5314 PHY Division Of Physics MPS Directorate for Mathematical and Physical Sciences |
Start Date: | September 15, 2018 |
End Date: | August 31, 2022 (Estimated) |
Total Intended Award Amount: | $120,000.00 |
Total Awarded Amount to Date: | $120,000.00 |
Funds Obligated to Date: |
|
History of Investigator: |
|
Recipient Sponsored Research Office: |
301 PLATT BLVD CLAREMONT CA US 91711-5901 (909)621-8121 |
Sponsor Congressional District: |
|
Primary Place of Performance: |
CA US 91711-5990 |
Primary Place of
Performance Congressional District: |
|
Unique Entity Identifier (UEI): |
|
Parent UEI: |
|
NSF Program(s): | Elem. Particle Physics/Theory |
Primary Program Source: |
|
Program Reference Code(s): |
|
Program Element Code(s): |
|
Award Agency Code: | 4900 |
Fund Agency Code: | 4900 |
Assistance Listing Number(s): | 47.049 |
ABSTRACT
This RUI award funds the research activities of Professor Brian Shuve at Harvey Mudd College.
The nature of the dark matter comprising most of the matter in the Universe, and the origin of the excess of matter over antimatter, are two major outstanding problems in particle physics. These phenomena can only be explained if there exist new particles and forces that have so far evaded detection; this collection of hitherto-unknown particles is known as the "hidden sector". Professor Shuve's research devises and investigates theories of hidden sectors with the aim of understanding more thoroughly how they can account for the unexplained questions of the Standard Model. Professor Shuve also studies the experimental manifestations of hidden sectors, proposing new empirical tests of hidden-sector particles as well as examining how signals of new particles could be hiding in the data of existing experiments. This research promotes progress in one of the most important aspects of fundamental science, namely the discovery of new physical laws and an improved understanding of the content and structure of the Universe, and thus advances the national interest. This project also has significant broader impacts: undergraduate student researchers are integral to the success of the project, and the involvement and training of students from under-represented groups will be prioritized. This research will lead to the development of tools for particle-physics research that are accessible to undergraduate researchers and made publicly available. Professor Shuve will also deliver public lectures to broaden awareness and interest in particle physics and will undertake outreach and recruitment activities for prospective first-generation college students and students from diverse backgrounds.
On a more technical level, Professor Shuve will perform detailed phenomenological studies of well-motivated, multi-component hidden sectors and will devise new strategies for experimental searches. One focus of the research will be on hidden sectors including right-handed neutrinos, which can account for neutrino masses, the baryon asymmetry, and dark matter. Professor Shuve's research will use simulated data and analytic calculations to map out sensitivities of current experiments as well as gaps in coverage. As a specific example, Professor Shuve will lead a signature-driven study of the prospects of discovering new hidden-sector particles at low-energy B-factory colliders and the Large Hadron Collider. This will result in the development and proposal of comprehensive search strategies for long-lived particles that enhance the prospects for experimental discoveries of new particles. Finally, Professor Shuve will study the cosmologically motivated parameter space of hidden sectors, particularly for freeze-in dark matter and leptogenesis in multi-component hidden sectors, and this will establish stronger connections between theoretical motivations of hidden sectors and experimental searches.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
PUBLICATIONS PRODUCED AS A RESULT OF THIS RESEARCH
Note:
When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external
site maintained by the publisher. Some full text articles may not yet be available without a
charge during the embargo (administrative interval).
Some links on this page may take you to non-federal websites. Their policies may differ from
this site.
PROJECT OUTCOMES REPORT
Disclaimer
This Project Outcomes Report for the General Public is displayed verbatim as submitted by the Principal Investigator (PI) for this award. Any opinions, findings, and conclusions or recommendations expressed in this Report are those of the PI and do not necessarily reflect the views of the National Science Foundation; NSF has not approved or endorsed its content.
Our current theory of elementary particles, the Standard Model, consists of many different particles and forces, but lacks the ability to explain the dark matter and matter-antimatter asymmetry seen in our universe. This project investigated theoretical extensions of the Standard Model that address these open questions, with an emphasis on how collections of new particles called "hidden sectors" affect the evolution of the early universe immediately after the Big Bang, and how these particles can be discovered in current or future experiments.
One major outcome has been the development of new experimental search strategies that can be used to discover these hypothesized hidden particles. The project focused on one particular type of particle called a long-lived particle (LLP). These are new particles that can be produced at colliders, travel distances of centimeters to meters (or more), and then decay, producing unusual but spectacular signatures that require dedicated analyses to find. This project led to a comprehensive study of LLPs at the Large Hadron Collider (LHC), including the development of a framework for analyzing and presenting results, an identification of gaps in coverage of current searches and ideas for new searches, and a study of the impact of proposed detector upgrades on LLP searches. This work enhances the possibility that the LHC will discover hitherto unknown particles that could be hiding in the current dataset.
The project also led to new developments for LLP searches at other experiments. In particular, lower energy electron-positron colliders can also search for LLPs, and this work laid out a framework for classifying signatures of LLPs at these experiments, and also proposed new search strategies. Our proposals can dramatically increase the range of hidden particles to which experimental searches are sensitive, ensuring that we are not missing any signs of dark matter or hidden sectors in currently available data. This work also investigated new possibilities for the discovery of hidden particles at experiments that study the rare decay of Standard Model particles containing strange quarks.
The second major outcome is an improved understanding of the cosmology of models of dark matter and the matter-antimatter asymmetry, with implications for experimental tests. In one popular and testable scenario in which the matter-antimatter asymmetry is connected to the origin of neutrino masses, we studied realistic versions of the model in which hidden neutrino masses arise dynamically due to a new Higgs boson. We found that the matter-antimatter asymmetry was dramatically suppressed in these models, such that the discovery of hidden neutrino states predicted by the model could actually disprove their role in generating the matter-antimatter symmetry. We studied and predicted new experimental signatures, showing how an observation of these signals in experiments could tell us about the new particles' role in generating the matter-antimatter asymmetry. We also studied how decays of new particles connected to neutrino masses could generate an asymmetry in a way that had not been identified before, and how this can alter the connection between theoretical predictions and experiments for cosmologically motivated models.
Finally, we developed an entirely new class of theories that can simultaneously account for dark matter and the matter-antimatter asymmetry. These scenarios, connected to popular freeze-in models of dark matter, predict new particles that are constrainted to be within reach of current or proposed experiments. Our framework also predicts different clumping properties of dark matter in galaxies compared to standard scenarios. We have studied several manifestations of the scenario, making concrete experimental predictions and proposals for new searches while elaborating on the physics responsible for the generation of the asymmetry in the early universe.
An important goal of the project was the establishment of an undergraduate-driven particle physics research group at Harvey Mudd College and the training of undergraduate students in vital research skills. This project led to publications with eight different undergraduate student co-authors and several student presentations at international conferences. Fourteen undergraduate student researchers were directly involved in the project, many of whom have gone on to or intend to go on to graduate study in fields such as physics, mathematics, and geophysics with implications for climate change. The results of this work have also had an impact on the local community via public talks.
Last Modified: 12/30/2022
Modified by: Brian Shuve
Please report errors in award information by writing to: awardsearch@nsf.gov.