17B Green Bank Observatory Time Allocation Committee Report

A total of 87 proposals requesting NSF funded “open skies” time were submitted to the Green Bank Observatory’s Robert C. Byrd Green Bank Telescope (GBT)  for semester 17B. 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 over-subscription 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 17B semester that have been reviewed by the Green Bank Observatory Telescope Allocation Committee (TAC).

A description of the 17B proposals accepted can be found on our NSF Open Skies Science Program page.

Statistics by Proposal Count

Total Proposals  87
Approved  49
Filler  8
Rejected  30
Hold  0
Over-subscription  1.8

Table 1

Statistics by Proposal Hours

Requested Time 6652.15 hours
Available Time 2767 hours
Approved 3187.5 hours
Filler 565.75 hours
Rejected 2898.9 hours
Over-subscription 2.1

Table 2

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 (observations between 8-18 GHz and 26.5-50 GHz), and excellent (observation 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 17A 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.