Call for SMA Science Observing Proposals

There is no active Call for Proposals. The most recent proposal deadline has passed, and the deadline for the subsequent period has not yet been determined. This document is for reference only.

Proposal Deadline
SMA Observing Time
Support for New Users
Number of Nights Available
Proposal Preparation
Proposal Evaluation
Accepted Proposals and SMA Observing

Proposal Deadline

The joint CfA-ASIAA SMA Time Allocation Committee (TAC) solicits proposals for observations for the period 2013 May 16 - 2013 Nov 15. Proposals must be submitted by:

Thursday, 7 February 2013, 11:00 HST (Hawaii)
Thursday, 7 February 2013, 16:00 EST (Cambridge, MA)
Thursday, 7 February 2013, 21:00 GMT
Friday, 8 February 2013, 05:00 CST (Taipei)

SMA Observing Time

The SMA is a joint project funded by the Smithsonian Astrophysical Observatory (SAO) and the Academia Sinica Institute for Astronomy and Astrophysics (ASIAA) and also includes the Institute for Astronomy (IfA) at the University of Hawaii as a partner institution. As of the 2011-B semester, the CfA and the ASIAA have merged their shares of time into a single pool on a trial basis. The time allocation ratios for the three SMA partners, CfA+ASIAA:IfA, are 85(72+13):15. Dedicated to excellence in scientific research and cooperation in the scientific community, the CfA and the ASIAA allocate their share of SMA observing time under an informal "open skies" policy. The CfA+ASIAA share of the SMA time is open to astronomers worldwide and is allocated by scientific merit.

In spite of the merged CfA-ASIAA time shares, PIs from Taiwan should select ASIAA as their proposal destination to facilitate book-keeping during the trial period. Astronomers proposing for IfA time should submit proposals diretly to the IfA, following their independent procedures. Collaborations among astronomers from different institutions are encouraged.

A new capability to cover a larger IF range which greatly enhances the choice of spectral lines observable in a single tuning has been operational for the 230 GHz band since the last (2012B) semester.

Operation in the 690 GHz band on a routine basis is under evaluation and is not being offered this semester due to reduced capabilities. An update will be provided if necessary.

Support for New Users

Number of Nights Available

On average, between five and six nights per week are allocated for routine science observations. Weather statistics suggest that approximately half of the useable time is suitable for observations in the 230 GHz and the 345 GHz bands each. Taking account of time devoted to testing, overhead, and lost to bad weather, the combined CfA+ASIAA share of the SMA time per semester averages about 41 nights each for the 230 GHz and the 345 GHz bands. The TAC uses these averages to set the approximate number of A-rated tracks.

The oversubscription rate is a function of target RA. The Figure below shows the distribution of target RA proposed in the past few semesters with notable peaks in the inner Galactic Plane.

Proposal Preparation

Existing SMA data

Proposers should query the SMA archive before planning observations to see if existing SMA data suit their scientific goals. Data from past SMA observations are archived by the CfA Radio Telescope Data Center and may be searched. SMA data are publicly available after a proprietary period of 15 months.

RA range and UV coverage

SMA observations are generally executed at night when the atmospheric phase noise is low and often continued into the early morning. Conditions are rarely suitable for afternoon observations. For 2013 May - 2013 November observing, long tracks will be feasible during at least half the semester for sources in the range of roughly RA=16h to 4h. Sources outside this RA range will also be considered if adequate justification is provided. However, since the array configuration schedule is set to accommodate the approved proposals, such observations might not be possible.

Many projects do not need full tracks for adequate uv coverage and/or sensitivity, and the TAC strongly encourages requests for snapshots and partial tracks.

Technical Information and Tools

Please see Array Status and Technical Information for up-to-date technical information about the SMA, including antenna configurations, correlator setups, receiver status, and new or updated SMA capabilities. The SMA maintains several online tools for planning SMA observations, available on the Tools page.

The Beam Calculator / Sensitivity Estimator is a particularly useful tool to estimate angular resolution, UV coverage and nominal sensitivities for different weather conditions (precipitable water vapor). Variations in weather may considerably impact actual sensitivities.

SMA observations require calibrator sources for bandpass, gain, and flux calibration. Quasars are generally used for bandpass and gain calibration; however, suitable calibrators may not be available for all parts of the sky particularly at the higher frequencies. See The Submillimeter Calibrator List. Solar system bodies are generally used for flux calibration but may not be available at all times of the year. Observers should show that their proposed observations can be adequately calibrated.

Proposals should provide clear justifications for the rms flux sensitivities, spectral resolutions, antenna configuration(s), weather conditions, and calibration strategies needed to achieve their science goals.

Proposal Forms and Proposal Submission

Proposals are submitted through each individual PI's SMA Project Account. The project account contains all information about an observer's proposals and projects, and will persist for reuse in future proposal cycles. All SMA project activities begin at the user's My Projects page. Project accounts may be created from the login page if necessary. (current SMAOC account holders do not need a separate project account)

Using the proposal submission facility, drafts may be created and edited at any time, but may only be submitted within a few weeks prior to the proposal deadline. Each proposal consists of an on-line cover form and technical information forms, and an attached scientific justification in PDF format. Proposals may be saved and edited on-line as often as needed prior to final submission. The scientific justification is limited to a maximum of two US-letter sized pages of text (11pt or larger) plus two US-letter sized pages of figures, tables and references.

Proposal Evaluation

Proposal selection is based on scientific merit and technical feasibility.

The TAC assigns each proposal a numerical score and recommends an amount of time to be allocated. The proposals are ranked and grouped into three categories: A (best effort to execute), B (may be executed as conditions permit), and C (will not be executed). Proposers are notified of their proposal rating by e-mail shortly after the TAC completes its work, typically within about ten weeks of the proposal deadline. Please see the TAC Procedures for more details of the TAC review process.

Accepted Proposals and SMA Observing

All accepted proposals are shared-risk, with no guarantee of success. Proposals accepted but not observed due to time constraints will not be carried over and must be resubmitted in response to a future call for proposals.

Principal investigators of successful proposals should be prepared to provide an observer on Mauna Kea. Most proposals are queue scheduled to maximize return based on the prevailing weather conditions and instrument status. The SMA scheduler decides what project will be observed each night. It is unlikely that visiting observers will execute their own project when present on Mauna Kea.

Data from SMA observations may be retrieved from the CfA's Radio Telescope Data Center archive for reduction.

Questions?

Please e-mail any questions about preparing and submitting proposals to propose [at] sma [dot] hawaii [dot] edu.