21A Proposal Call
The Green Bank Observatory (GBO) invites scientists to
participate in the 2021A Semester
Call for Proposals for the Green Bank Telescope (GBT).
The submission deadline for Semester 2021A proposals is
Monday, 3 August 2020, at 17:00 EDT (21:00 UTC).
The entire proposal call can be found on this page.
The GBT is happy to announce a new opportunity for joint observations with SOFIA. Up to three percent of the U.S. Guest Observer time on SOFIA will be made available for requests in GBT proposals.
Receiver availability for the 2021A semester will be determined by those highly ranked proposals accepted in Group A.
The GBT only accepts large proposals once per year at the February proposal deadlines. We no longer accept GBT large proposals at the August proposal deadlines. The next large proposal deadline for the GBT after this call will be for the 2021B semester. This new policy ensures equality for the reviews of all large proposals that can be scheduled across a full year.
Recall that all large proposals are restricted to using no more than 50% of the open skies time available under any weather category (poor, good, excellent) at any LST during any semester.
New Regular, and Large proposal size definitions for the GBO:
- 0-8 GHz (Any weather)
- Regular: < 400 hours and lasting ≤ 1 year
- Large: ≥ 400 hours or lasting >1 year
- 8-18 and 27.5-50 GHz (Good weather)
- Regular: < 200 hours and lasting ≤ 1 year
- Large: ≥ 200 hours or lasting >1 year
- 18-27.5 and > 50 GHz (Excellent weather)
- Regular: < 100 hours and lasting ≤ 1 year
- Large: ≥ 100 hours or lasting >1 year
- Fixed and Monitoring proposals
- Regular: < 200 hours and lasting ≤ 1 year
- Large: ≥ 200 hours or lasting >1 year
The GBO encourages proposals that take advantage of the GBT’s unique capabilities across 0.29 to 116.2 GHz frequency range. (Coverage is not available for 2.65-4.0 GHz, 15.8-18.0 GHz, and 49.9-67.0 GHz)
Key science areas include, but are not limited to:
- Low column density HI (NHI ≈1017 cm-2 galactic and extragalactic)
- astrochemistry
- cosmology
- fast radio bursts
- galaxy and cluster evolution
- pulsars (searches and timing)
- radio recombination lines
- solar system science
The GBO also encourages the submission of high risk, high reward proposals requiring GBT observing time.
There are approximately 1000 hours of excellent weather (18-27.5 and > 50 GHz) available each semester for both open skies and sponsored time. Prior commitments typically account for half of this time which leaves only 500 hours available for new requests each semester.
Instrumentation news:
- The PFS radar backend has been retired.
- A new X-band receiver is expected to begin commissioning in the 21A semester.
- There will be two new prime focus receivers undergoing testing and commissioning on the GBT during the 21A semester. As a result the Prime Focus 342 MHz feed is not expected to be available on a regular basis during the 21A semester.
Filler time proposals which can take advantage of gaps in the GBT schedule are also encouraged.
Triggered proposals can be submitted for studies of transient objects such as fast radio bursts, near Earth asteroids, comets, and other transients.
All proposals should state why the GBT is necessary for the requested observations in both the abstract and science justification.
We strongly encourage proposers to carefully read through the “News and Opportunities” section of the proposal call.
Proposals requesting the GBT as part of High Sensitivity Array (HSA), and Global 3mm VLBI Array (GMVA) should be submitted through the Very Long Baseline Array’s call (available here).
We wish to remind proposers of continuing opportunities for joint observations with the Chandra X-ray Observatory, the Hubble Space Telescope, the Swift Gamma-Ray Burst Mission, the Fermi Gamma-ray Space Telescope and XMM-Newton.
Proposal preparation and submission remain via the NRAO Proposal Submission Tool (PST) available at NRAO Interactive Services. Note that use of the PST requires registration. Proposers who need assistance with proposal preparation or have questions regarding the Call or GBT capabilities should contact Observatory staff via the Helpdesk.
Please note that the GBT is scheduled in 15 minute (0.25 hour) increments and that all proposals should request time appropriately. Time requests will be rounded down to the nearest 0.25 hour increment.
News and Opportunities
The 3 August 2020 deadline is for the 2021A Semester observing period on the GBT:
1 February 2021 – 31 July 2021
Details of all GBT observing modes are in The Proposer’s Guide for the Green Bank Telescope. Proposers should also consult the more general document The Performance of the GBT: A Guide for Planning Observations. Proposers should make sure that they are familiar with the latest versions of these documents before writing their proposal.
Joint Observations with SOFIA
By agreement with the GBO, SOFIA may award up to 5% of GBO open skies observing time. Similarly the GBO Time Allocation Committee may award up to 3% of the U.S. Guest Observer Time on SOFIA. See the Joint Observations with SOFIA page for details.
Large Proposals
Beginning with the 2020B semester the GBT will only accept large proposals once per year at the February proposal deadlines. We will no longer accept GBT large proposals at the August proposal deadlines. There will not be a large proposal call for 2021A for the GBT. The next large proposal deadline for the GBT after this call will be for the 2021B semester. This new policy ensures equality for the reviews of all large proposals that can be scheduled across a full year.
Instrumentation
The GBT receivers, backends, and observing modes that are available in Semester 2018B are listed in Tables 1 and 2 below.
| Receiver | Frequency Range | Note |
|---|---|---|
| Prime Focus 1 | 290 – 395 MHz 385 – 520 MHz 510 – 690 MHz 680 – 920 MHz | |
| Prime Focus 2 | 910 – 1230 MHz | |
| L-band | 1.15 – 1.73 GHz | |
| S-band | 1.73 – 2.60 GHz | |
| C-band | 3.8 – 8.0 GHz | linear only, see below |
| X-band | 5 – 11.6 GHz | |
| Ku-band | 12.9 – 15.4 GHz | |
| K-band Focal Plane Array (KFPA) | 18 – 26.5 GHz | 7-pixel array |
| Ka-band | 26 – 39.5 GHz | |
| Q-band | 38.2 – 49.8 GHz | |
| W-band | 67 – 93.3 GHz | |
| Argus | 75 – 115.3 GHz | 16-pixel array |
| MUSTANG-2 | 90 GHz | shared-risk, private PI instrument |
| Backend | Observing Mode | Note |
|---|---|---|
| VEGAS | continuum, spectral line, pulsar | |
| DCR | continuum | |
| MARK6 Disk Recorder | VLBI | |
| JPL Radar backend | radar | Private PI instrument, open for public use |
| Breakthrough Listen | Private PI instrument, shared risk |
C-band: Proposals wishing to use the GBT C-band receiver should only use linear polarization outputs. The circular polarization of the receiver is currently not preforming correctly and we will not accept any proposals to use the circular polarization output of this receiver.
C-band VLBI on the GBT: The GBO will only accept proposals using the GBT C-band receiver for VLBI Stokes I continuum observations (the observations will need to be done using full Stokes just to calibrate Stoke I). Please see the HSA section of the Long Baseline Observatory call (available here) for proposals for more details.
VEGAS, Continuum: All modes of VEGAS may now be used for continuum observations. The Proposal Submission Tool has not been updated to reflect this situation. Proposers should use the spectral line modes of VEGAS to choose the desired bandwidth and then note in the technical justification that the observations will be for continuum measurements.
VEGAS, Pulsar: VEGAS pulsar modes have been released.
Argus: Observers interested in using the Argus instrument should see http://www.gb.nrao.edu/argus/ for further information.
VLBI: Proposers should clearly justify the need for the GBT in the text of the proposal. All Very Long Baseline Interferometry (VLBI) proposals requesting the GBT should include any needed setup and overhead time in the time request of their proposals. C-band VLBI observers should see the C-band VLBI note above.
MUSTANG-2: The GBO will accept proposals for shared risk observations using the MUSTANG-2 instrument at the proposal deadline. The GBO cannot guarantee that MUSTANG-2 will be cold at the start of scheduled observing due to low observing elevations or rotations of the turret from prior observations. Cool down time for MUSTANG-2 observations should be included in the overhead for MUSTANG-2 observations. All MUSTANG-2 proposals must have permission from the instrument development team.
Breakthrough Listen backend: The Breakthrough Listen project is making its backend available for shared-risk observations during the 2021A semester. The instrument consists of a cluster of 64 Titan X and 1080 GPU-based servers capturing 8-bit baseband voltages over up to 12 GHz of instantaneous bandwidth. Data rates are typically tens of TB/hr but a pipeline is available to generate spectra with adjustable frequency (> 3 Hz) and time (> 350 μs) resolutions, with possible science applications including fast radio transients, pulsar observations, stellar flares, SETI, etc. Before submitting a proposal, proposers must obtain permission from the Breakthrough Listen team at Berkeley SETI Research Center. The team will consult on proposal preparation and data analysis. Any data acquired using the backend will be proprietary to the proposer per the standard GBO policies.
More information including a technical description of the backend and team contact details can be found here.
Observing and Scheduling Constraints
The GBT is scheduled by the Dynamic Scheduling System (DSS). The DSS system is fully described in the GBT Proposer’s Guide and the GBT Observer’s Guide.
Session lengths: Proposers should be aware that long scheduling blocks (more than 6 hours) become increasingly difficult to schedule as a result of the transition to reduced open skies time by the NSF. Proposers must clearly state in the technical justification section how their project could be scheduled in smaller observing blocks that would more easily fit within the GBT scheduling constraints. This is especially critical for proposals that require fixed or coordinated observing dates, e.g. VLBI observations, pulsar monitoring, radar, etc.
Mapping: If you are considering mapping with the GBT such that there are major turns or moves (end of rows in raster map, change in position for pointed maps, etc.) that occur with a cadence faster than every 30 seconds, you will need to consult with a GBT support scientist to ensure that the GBT can safely withstand the stresses induced by the mapping motions.
“Fixed” and “Windowed” Observations: Due to varied pressures on the GBT’s scheduling resulting from the transition to reduced open skies by the NSF, fixed time observations (e.g. VLBI, pulsar transit observations, etc.) and windowed observations (e.g. monitoring observations) will likely have to be ranked at least in or near the top 10-15% of all AUI telescope proposals in order to be accepted.
Instrument Availability: The availability of GBT Gregorian receivers and prime focus feeds will be based on demand from the highly ranked (Group A) proposals. Some receivers and feeds may be available only for a few short, two or three week periods during the semester.
Observing Team Members: We would like to remind all project teams of the Green Bank Observatory policy that all observers must be listed as a member of the project team in the GBT Dynamic Scheduling System.
Also, we would like to remind all observers that they should not log into any GBO computing system using another person’s account. Co-Is and students are required to have their own GBO login and account if they are to participate in observing and data reduction.
Scheduling Increments: Please note that the GBT is scheduled in 15 minute (0.25 hour) increments and that all proposals should request time appropriately. Time requests will be rounded down to the nearest 0.25 hour increment.
GBT Proposal Preparation
Proposers should consult the The Performance of the GBT: A Guide for Planning Observations and the GBT Observer’s Guide. All proposers, including pulsar proposers, should use the GBT Sensitivity Calculator. Please see the Calculator’s User’s Guide for instructions. The Sensitivity Calculator results can be cut and pasted into the Technical Justification section of the proposal. This will streamline the creation of your Technical Justification and will increase your chances of getting a positive technical review. If you are planning on making maps with the GBT, you should use the GBT Mapping Calculator tool.
The GBT observing policies describe the telescope’s remote observing restrictions.
Proposers requesting GBT participation in High Sensitivity Array (HSA), Very Long Baseline Array (VLBA), or Global Millimeter Very Long Baseline Interferometry (GMVA) observations should consult the VLBA, HSA, and GMVA Proposal Call.
RFI
RFI Monitoring Scans: The most recent RFI monitoring scans for the GBT can be found here. These scans provide information on the frequencies that may encounter RFI.
470-700 MHz RFI: Digital TV transmissions above 470 MHz will make observing very difficult with the 450 and 600 MHz feeds of the PF1 receiver. Available RFI plots do not show the strength of these signals as the RFI overpowers the system: the plot intensities are estimated to be too low by a factor of up to 10 to 50. Observers should consult the GBT support scientists before submitting a proposal for these feeds. Also, “TV Whitespace” usuage of these frequencies is expected to begin in 2018.
Schools and Workshops
Observer Training Workshops: The Green Bank Telescope (GBT) Remote Observer Training Workshop will provide the essential skills and knowledge needed to use the GBT and maximize its scientific output. It is intended for experienced astronomers who need to learn the specifics of observing with the GBT. After completing the workshop, an attendee will be certified to use the GBT as a remote observer. The workshop will focus on hands-on training in the observing techniques most relevant to participants (e.g. high frequency map, continuum, pulsar, etc.).
These workshops will be held several times a year and will complement traditional on-site training. The next workshop will be held October 13-14, 2020 and will be held virtually. More information can be found here.
Single Dish Training School: The Green Bank Telescope (GBT) Single Dish Training School will provide graduate students, post-docs, and experts in other fields of astronomy with both knowledge and practical experience of the techniques and applications of single-dish radio astronomy using the GBT as the primary example. The school will be based around an intensive series of lectures from experts, as well as hands-on radio-astronomy projects and tutorials. Topics to be covered include radio telescope fundamentals, key single-dish science areas, observing and calibration techniques, the impact of weather, the GBT observing procedures and software, and data reduction.
The school will be held once per year. An intensive GBT remote observer training workshop will be held immediately following the school for those who wish to obtain remote observing certification. The next school will be held in Summer 2021. More information can be found here.
Continuing Opportunities
Joint Observations with SOFIA
By agreement with the Green Bank Observatory, SOFIA may award up to 5% of GBT open skies observing time. Similarly the GBT Time Allocation Committee may award up to 3% of U.S. Guest Observer Time on SOFIA. See the Joint Observations with SOFIA page for details.
Joint Observations with XMM-Newton
By agreement with the Green Bank Observatory, detailed in a Memorandum of Understanding, the XMM-Newton Project may award up to 3% of GBT open skies observing time. Similarly the GBT Time Allocation Committee may award up to 150 ks of XMM-Newton time per year. See the Joint Observations with XMM-Newton page for details.
Joint Observations with Chandra X-ray Observatory
In previous semesters, the community has had the opportunity to propose for observing time on NRAO facilities through a joint program with the Chandra X-ray Observatory. The Green Bank Observatory will continue with this program and will allocate up to 3% of the open skies time to highly ranked proposals that request time on both HST and the GBT. Proposers to the GBO will have the opportunity to request time on Chandra, to be awarded on the recommendation of the GBO Telescope Allocation Committee (TAC) and approved by the GBO Director. Up to 120 ksec will be made available to GBO/LBO/NRAO proposers annually. See the Joint Observations with Chandra page for details.
Joint Observations with the Hubble Space Telescope (HST)
By agreement between the NRAO (and continued honoring by GBO) and the Space Telescope Science Institute, STScI will be able to award up to 3% of the available open skies time to highly ranked proposals that request time on both HST and the GBT. In return, STScI has offered 30 orbits of HST time for allocation by the GBO/LBO/NRAO TAC to proposals submitted for the GBO deadlines for Semester 2020B and Semester 2021A. See the Joint Observations with HST page for details.
Joint Observations with Swift Gamma-Ray Burst Mission
To foster correlative observations, a joint Swift/NRAO observing program was established, detailed in a Memorandum of Understanding. The GBO will continue to honor this agreement. By this agreement, the Swift Program permits GBO/LBO/NRAO to award up to 300 kiloseconds of Swift observing time per year. Similarly, GBO/LBO/NRAO permits the Swift Guest Investigator (GI) Program to award GBO observing time. See the Joint Observations with Swift page for details.
Joint Observations with Fermi Gamma-ray Space Telescope
We remind the community that it is possible to propose for observing time on the GBT through the Fermi Gamma-ray Space Telescope Joint Proposal Opportunity or the Cooperative Proposal Opportunity. See the Joint Observations with Fermi page for details.
Joint Proposals Between the GBT and NRAO
Observing programs that require combinations of the GBT, VLBA, and/or the VLA should submit a proposal for each of the requested telescopes, with a clear justification for each, as has been the case to date. The proposals will be reviewed as before and considered jointly by the Time Allocation Committee. VLBI proposals which request the GBT or VLA (or the HSA, for example) as elements of the VLBI array do not need separate proposals—those telescopes can be selected as separate VLBI stations from a VLBA/HSA proposal.
Other Proposal Opportunities
The GBO would like to make users aware that there are additional proposal opportunities as follows:
High Risk Proposals: As a means of maximizing its scientific impact through cutting-edge observations, the Observatory encourages the submission of high-risk/high-reward proposals. The high risk/high reward should be designated in the abstract of the proposal and in the science justification.
Filler Programs: Some programs that are not time critical or require highly subscribed LST ranges can request designation as a “filler program.” Such programs may be able to take advantage of gaps in the GBT schedule, but there no guarantee that any GBT time will be allocated. Proposals requesting a designation as filler should do so in the proposal abstract and in the science justification. All filler programs will be given a ranking of C.
Triggered Proposals: Observations for unknown sources that would be triggered by a celestial event (e.g. near Earth asteroid, comet, fast radio burst, etc.) can be submitted as a triggered proposal. Any accepted triggered proposal will have proprietary rights to observations over any DDT proposal.
Further information about each of these programs can be found here.
21A Proposal Call Results
A total of 80 proposals requesting NSF funded “open skies” time were submitted to the Green Bank Observatory’s Robert C. Byrd Green Bank Telescope (GBT) for semester 21A. Proposals are reviewed on a competitive basis with a panel review system (see Proposal Review System). Below are the statistics by proposal count and hours. The oversubscription is the ratio of the number of submitted proposals to the number of approved proposals. The pressure is the ratio of the requested time to the available time in hours. Here we only include proposals submitted for the 21A semester that have been reviewed by the Green Bank Observatory Telescope Allocation Committee (TAC).
A description of the 21A proposals accepted can be found in our NSF Open Skies Science Program section below.
| Total Proposals | 82 |
|---|---|
| Approved | 31 |
| Filler | 11 |
| Rejected | 36 |
| Hold | 0 |
| Withdrawn | 0 |
| Oversubscription | 2.6 |
| Requested Time | 5048 h |
| Available Time | 2664.5 h |
| Approved | 1383.75 h |
| Filler | 1046 h |
| Rejected | 2525.75 h |
| Pressure | 1.9 |
GBT Pressure Plots
Observations in high frequency bands require better weather conditions than observations in lower frequency bands. The GBT uses three weather categories:
- poor – for observations below 8 GHz
- good – for observations between 8-18 GHz and 26.5 – 50 GHz
- excellent – for observations in the 18-26.5 GHz band and above 50 GHz
The first three figures below show the pressure plots for each these weather categories. The last figure includes all weather categories. The grey horizontal line shows the total available hours. The letters A, B, and C correspond to the priorities assigned by the TAC where A and B are approved time and C is filler time. Carryover is time allocated by a TAC from a previous semester that is being executed in the 18B semester.
GBT Observation Preparation
Please use the GBT Dynamic Scheduling System (DSS) to enable observing sessions, select observers for your project, and enter your blackout dates. The DSS Home Page has additional information about the DSS. See GBT Observing for information about how to prepare for your observations.
Please note that the DSS uses the average Right Ascension (RA) and Declination (Dec) of all sources within a session. The average RA and Dec will be used to determine when the session can be scheduled. You will need to carefully check the RA and Dec, along with the minimum and maximum session lengths, to make sure that these values are satisfactory and will allow all your sources to be observed before enabling the session.
21A Science Program
A total of 80 proposals requesting NSF funded “open skies” time were submitted to the Green Bank Observatory’s Robert C. Byrd Green Bank Telescope (GBT) for the August 3, 2020 semester 21A deadline. The table below summarizes the approved observing programs. Listed are the PI name, proposal ID, proposal title, maximum hours approved and proposal type (Regular, Triggered, Large or External). Proposals from previous semesters that were awarded time in the 21A semester are included. The table also includes HSA and GMVA proposals that were awarded time on the GBT as a VLBI station as well as proposal accepted via external agreements with CHANDRA, Hubble Space Telescope, FERMI and Swift.
For each approved program, the Proposal Finder Tool will have access to its author, title, abstract and total approved hours.
A description of the Time Allocation Committee report for 21A can be found in the Proposal Call Results section above.
| PI | ID | Title | Hours | Type |
|---|---|---|---|---|
| Andreon, Stefano | GBT20B-020 | A intermediate mass cluster kept at the epoch of entropy growth | 13 | Regular |
| Archibald, Anne | GBT21A-216 | Continued Timing of a Millisecond Pulsar in a Stellar Triple System | 25 | Regular |
| Baczko, Anne-Kathrin | GMVA21A-233 | Resolving the twin-jet base in NGC 1052 | 33 | Regular |
| Brinks, Elias | GBT21A-237 | Radio Continuum — Star Formation Rate relation: Filling the Gaps | 39.75 | Regular |
| Brodwin, Mark | GBT20B-212 | MUSTANG-2 Observations of the Highest-Richness MaDCoWS Clusters at 0.8 < z < 1.6 | 56.5 | Regular |
| Burkhardt, Andrew | GBT21A-286 | Constraining Aromaticity in Targeted Chemical Laboratories Throughout TMC-1 | 36 | Regular |
| Busch, Michael | GBT21A-088 | A GBT Search for the Diffuse Molecular Gas Disk in Absorption | 177 | Regular |
| Butterfield, Natalie | GBT21A-190 | Investigating the Star Forming Potential of the Galactic Bar Dust Lanes | 8 | Regular |
| Cameron, Andrew | GBT21A-136 | Continued observations of an eccentric, relativistic binary pulsar. | 57 | Regular |
| Das, Sanskriti | GBT21A-377 | Is circumgalactic HI ubiquitous? A deep search around 4 nearby galaxies | 172 | Regular |
| Demorest, Paul | GBT20B-307 | The North American Nanohertz Observatory for Gravitational Waves | 870 | Large |
| Di Teodoro, Enrico | GBT21A-296 | Measuring 12CO(1-0) emission in the Milky Way's Nuclear Wind | 31 | Regular |
| Emig, Kimberly | GBT21A-292 | Feedback from Diffuse Ionized Gas in the Cygnus X Star-Forming Region | 108 | Regular |
| Freeman, Pamela | GBT21A-039 | Complex Organics Vs. Warm Carbon Chains in High Mass Star Forming Regions | 13 | Regular |
| Freire, Paulo | GBT21A-167 | Following a potentially super-massive pulsar in NGC 6624 | 24 | Regular |
| Gajjar, Vishal | GBT21A-328 | High-frequency followup of newly active CHIME repeaters with the GBT | 40 | Triggered |
| Ginsburg, Adam | GBT21A-086 | MUSTANG Galactic Plane survey: The inner Galaxy (B sem) | 81 | Regular |
| Greve, Thomas | GBT21A-299 | MUSTANG-2-RAGERS: Tracing Proto-Cluster Growth over Cosmic Time | 10 | Regular |
| Grossan, Bruce | GBT21A-230 | Multi-Frequency, Simultaneous FRB121102 Observations -A New Approach (Reprise) | 49.5 | Triggered |
| Issaoun, Sara | GMVA20B-269 | Sharpening the Source Model for Sgr A* with GMVA+ALMA | 10 | Regular |
| Jones, Kristen | GBT21A-325 | SURVEYING COOL GAS IN HIGH-Z SDSS-III/BOSS TYPE-2 QUASARS USING HI-ABSORPTION | 24.5 | Regular |
| Kaplan, David | GBT21A-365 | A Search for FRBs from the Pulsar Wind Nebula left by the Peculiar SN 2012au | 12 | Regular |
| Karunakaran, Ananthan | GBT20B-045 | The HI content of Field Ultra-Diffuse Galaxies in SMUDGes: Final Campaign | 159 | Regular |
| Karunakaran, Ananthan | GBT21A-388 | Mass dependence of Gas Content in LSB Satellite Galaxies | 60 | Regular |
| Karunakaran, Ananthan | GBT21A-389 | The HI content of Field Ultra-Diffuse Galaxies in SMUDGes | 63 | Regular |
| Kim, Jae-Young | GMVA20B-204 | First subparsec-scale imaging of the new TeV gamma-ray radio galaxy 3C 264 | 8 | Regular |
| Kino, Motoki | GMVA20B-066 | Ultra-deep imaging of the stratified jet base of Cygnus A | 15 | Regular |
| Kramer, Michael | GBT20B-214 | Timing and General Relativity in the Double Pulsar System | 101 | Regular |
| Krishnarao, Dhanesh | GBT21A-363 | Radio Recombination Lines: Constraints on the Fermi Bubble Shell | 31.5 | Regular |
| Kulterer, Beatrice | GBT21A-199 | Deuterated methanol with ARGUS in the prestellar core L1544 | 32 | Regular |
| Kumar, Pravir | GBT20B-248 | Uncovering and studying the southern repeating fast radio burst population | 57 | Regular |
| Kumar, Pravir | GBT21A-186 | Uncovering and studying repetition in the ASKAP FRBs population | 114 | Regular |
| Leisman, Lukas | GBT21A-034 | FLAG HI Mapping of Diffuse HI Emission in the Leo Cloud of Galaxies | 67 | Regular |
| Lockman, Felix | GBT21A-240 | Tracing the Neutral Gas in the Nuclear Wind | 301 | Regular |
| Lu, Rusen | GMVA20B-220 | Jet Meets Black Hole in M87: Breaking New Ground with GMVA+ALMA | 28 | Regular |
| MacDonald, Nicholas | GMVA20B-145 | Disorder vs. Order: Discerning the nature of the magnetic field in PKS 1510-089 | 5 | Regular |
| Marcote, Benito | G20B001 | Solving the puzzling persistent emission associated to FRB 121102 | 13 | Regular |
| Mason, Brian | GBT21A-376 | A Multi-Scale, Multi-Wavelength Study of Dust in Molecular Cloud Filaments | 27.5 | Regular |
| McGuire, Brett | GBT19B-047 | Continuing An Extremely Deep GBT Survey of TMC-1 | 396 | Large |
| Minchin, Robert | GBT21A-352 | A Drift Scan Survey for Gas in Galaxies, the Milkey Way, Pulsars, and FRBs. | 197.25 | Regular |
| Mroczkowski, Tony | GBT21A-123 | MUSTANG2 Imaging of the AGN-driven Cavities in MS 0735.6+7421 | 32 | Regular |
| Murphy, Eric | GBT21A-250 | MUSTANG-2 SFRS: 3mm Maps of Star Formation in Nearby Galaxies | 14 | Regular |
| Orienti, Monica | VLBA21A-014 | Unveiling particle acceleration regions in the X-ray emitting hotspot 3C227 West | 6 | Regular |
| Pineda, Jaime | GBT21A-238 | Ions vs Neutrals in a Dense Core | 18 | Regular |
| Pingel, Nickolas | GBT21A-130 | Utilizing FLAG to Map the Diffuse HI in the Circumgalactic Medium of NGC891 | 95.25 | Regular |
| Pingel, Nickolas | GBT21A-131 | Continuing the FLAG Imaging of Eridanus (FIEri) Project | 52 | Regular |
| Pleunis, Ziggy | GBT21A-375 | Searching for repetitions from fast radio bursts with frequency drifts | 30 | Regular |
| Plume, Rene | GBT20B-027 | Complex Organics Vs. Warm Carbon Chains in High Mass Star Forming Regions | 17.25 | Regular |
| Ransom, Scott | GBT21A-344 | Long Term Timing of 62 Recycled Pulsars in Bulge Globular Clusters | 40 | Regular |
| Rivilla, Victor M. | GBT20B-111 | Confirming selective collisional-pumped excitation of ethanimine in G+0.693 | 3 | Regular |
| Sakemi, Haruka | GBT21A-188 | Continuum Observation of Radio Nebula W50 | 31.25 | Regular |
| Schmiedeke, Anika | GBT21A-222 | Mustang-2 mapping of isolated cores on the verge of star formation | 16.25 | Regular |
| Scibelli, Samantha | GBT21A-176 | High Resolution C18O ARGUS Mapping toward Prestellar Cores in Taurus | 20 | Regular |
| Singal, Jack | GBT19A-083 | How Bright is the Radio Sky? A 310 MHz Absolute Map | 30 | Regular |
| Smith, Evan | GBT21A-372 | Observing and Mapping Solar Radio Bursts with FLAG | 4 | Regular |
| Stairs, Ingrid | GBT20B-213 | Understanding the Magnetic Field Configuration in a Moding, Oscillating Pulsar | 27 | Regular |
| Stark, David | GBT20B-033 | HI-MaNGA: HI Followup for MaNGA Galaxies | 580 | Large |
| Suresh, Akshay | GBT21A-332 | A Pilot Search for Galactic Transients from VLASS-identified Candidate Sources | 12 | Regular |
| Svoboda, Brian | GBT20B-295 | Dense gas in cold clumps: a pilot GBT/Argus Galactic Plane survey | 40 | Regular |
| Swiggum, Joseph | GBT21A-367 | Completion of the GBT All-Sky 350-MHz Pulsar Survey | 200 | Regular |
| Tam, Pak Hin | GBT21A-341 | Discovering the pulsars of four promising TESS-selected redback candidates | 3.75 | Regular |
| van ‘t Hoff, Merel | GBT21A-092 | Carbon-grain Sublimation: A New Top-down Component of Protostellar Chemistry | 23.5 | Regular |
| Wampfler, Susanne | GBT21A-353 | Ammonium salts – the solution to the apparent nitrogen deficiency in comets? | 28 | Regular |
| Wilner, David | GBT21A-079 | Large Dust Grains in the Vega Debris Disk | 16 | Regular |
| Yang, Chentao | GBT21A-093 | Confirming the nature of a 380GHz H2O maser disk in a lensed quasar at z=3.91 | 49 | Regular |
| Yu, Qingzheng | GBT21A-245 | Probing the HI Content of Merging Galaxies in MaNGA | 10.75 | Regular |