| NSF Org: |
AST Division Of Astronomical Sciences |
| Recipient: |
|
| Initial Amendment Date: | May 29, 2015 |
| Latest Amendment Date: | March 20, 2019 |
| Award Number: | 1440338 |
| Award Instrument: | Standard Grant |
| Program Manager: |
Nigel Sharp
nsharp@nsf.gov (703)292-4905 AST Division Of Astronomical Sciences MPS Directorate for Mathematical and Physical Sciences |
| Start Date: | June 1, 2015 |
| End Date: | May 31, 2022 (Estimated) |
| Total Intended Award Amount: | $4,999,157.00 |
| Total Awarded Amount to Date: | $5,998,558.00 |
| Funds Obligated to Date: |
FY 2019 = $999,401.00 |
| History of Investigator: |
|
| Recipient Sponsored Research Office: |
1608 4TH ST STE 201 BERKELEY CA US 94710-1749 (510)643-3891 |
| Sponsor Congressional District: |
|
| Primary Place of Performance: |
LeConte Hall Berkeley CA US 94704-5940 |
| Primary Place of
Performance Congressional District: |
|
| Unique Entity Identifier (UEI): |
|
| Parent UEI: |
|
| NSF Program(s): | MID-SCALE INSTRUMENTATION |
| Primary Program Source: |
01001920DB NSF RESEARCH & RELATED ACTIVIT |
| Program Reference Code(s): |
|
| Program Element Code(s): |
|
| Award Agency Code: | 4900 |
| Fund Agency Code: | 4900 |
| Assistance Listing Number(s): | 47.049 |
ABSTRACT
The POLARBEAR experiment measures polarized fluctuations in the Cosmic Microwave Background (CMB) to search for the signature of gravitational waves from inflation, potentially opening a window on the universe a fraction of a second after the Big Bang. This is a major quest of current physics and astronomy and has broad implications for our understanding of the origin and history of the universe. AST has previously funded the construction, commissioning, and initial operations of the first POLARBEAR 3.5m-diameter telescope at the Atacama desert site near ALMA in Chile. The current award will support commissioning and operations of a second telesope under partnership with the Simons foundation and other collaborating institutions in the US, Japan, Canada, and the UK. The award will support advanced traning for students in instrumentation and facility development. Other broader impacts include educational programs for K-12 students and the general public.
Science goals in addition to B-mode gravitational waves include a search for massive neutrinos, a map of large scale structure in the universe via gravitational lensing, and constraints on the primordial helium abundance and the effective number of relativistic species.
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.
The Simons Array project has three telescopes which are designed to map the cosmic microwave background (CMB) radiation to search for the signature of a sudden, exponential expansion of space at the time of the BIg Bang. This event is called inflation, and currently there is circumstantial evidence that it occurred but scientists would like to discover direct evidence for inflation.
Inflation would cause a swirling pattern of polarization in the CMB referred to as "B-modes" which are created by gravitational waves produced by inflation. If we are able to see the B-mode signal, we will have proven that inflation occurred and we can also measure the characteristic energy scale of inflation.
Simons Array telesocpes have a 2.5 meter diameter primary mirror which give a 3.4 arc-minute angular resolution at 150 GHz. The telescopes can image gravitational lensing of the CMB which is scientifically very interesting in its own right, but it is also a signal that has to be subtracting from any inflationary signal.
The CMB lensing signal can give us a measure of how much Dark Matter there is in the universe. In turn, we can then also measure the mass of neutrino particles since the neutrinos as a form of Dark Matter.
Each Simons Array telescope has a focal-plane with 7,588 bolometer detectors cooled to 0.25K above absolute zero temperature. Each pixel in the focal plane is coupled to the telescope with a hemispherical silicon lenslet. Underneath the lenslet, there is a silicon wafer with lithographed, superconducting antennas, filters, and detectors.
During the funded period, we brought two receivers to operational status and we have been taking science data with the first telescope/receiver. We were significantly delayed by COVID-19, since we were not able to visit Chile or had reduced personnel for the past several years.
We plan to propose for further funds to complete our planned hardware and observation scope.
Last Modified: 10/03/2022
Modified by: Adrian T Lee
(2)--rgov-66x44.jpg)
Please report errors in award information by writing to: awardsearch@nsf.gov.
