MAGIC observation proposals (Cycle 18)
MAGIC OBSERVATIONS PROPOSED BY EXTERNAL SCIENTISTS
The MAGIC collaboration encourages individual external scientists to propose observations to be performed with the MAGIC telescopes. Observation time will be granted by the Time Allocation Committee (TAC) based on scientific merit.
There is no pre-allocated share for internal or external members.
The observation cycle 18 spans 12 moon periods, from 2023, March 5 to 2024, February 21.
The deadline to submit the MAGIC proposals is 2022 November 4th at 23:59 UT. The evaluation of the proposals will be performed within November and December 2022 and the PIs will be informed on the outcome of the evaluation soon after.
MAGIC is not an open observatory, and the analysis of the data requires specific expertise and tools. Some MAGIC members assigned by the collaboration or proposed by the external scientist will be supporting the external projects throughout the entire procedure of proposal submission, and (if the observation time is granted) data reduction and publication.
The details on the authorship of the publications will be discussed and agreed before the submission of the observation proposal. The MAGIC collaboration shall be included in the authors' list of the publications reporting these data results for the first time.
GUIDE FOR PROPOSAL SUBMISSION
General Information
The amount of observations performed yearly with the MAGIC telescopes are about 1000 hours in dark time, depending on weather conditions and technical access during that year. Additionally, moon observations can add up to 400 hours.
The amount of observations performed yearly with the MAGIC telescopes are about 1000 hours in dark time, depending on weather conditions and technical access during that year. Additionally, moon observations can add up to 400 hours. The former condition guarantees the best performance, the latter a somewhat reduced performance depending on the moon level (see below).
According to the XMM-MAGIC joint program, the MAGIC TAC can award up to 42 hours (150 ks) of XMM time for the Cycle 18 proposals requesting XMM observations.
Preparation to Submission
The deadline for proposal submission is November 4th at 23:59 UT. In any case, we encourage external scientists to contact the MAGIC Physics coordinator
(
antonio.stamerra@inaf.it ),
before October 15th.
The physics coordinator will check if the proposed observations have already been performed, or if they are planned as part of a running project within the MAGIC collaboration.
To enhance the feasibility of the proposal,
the specifics of the observations should be examined and discussed with scientists from the MAGIC collaboration well before the proposal submission deadline.
The submission of the proposals for MAGIC observations is performed through the
MAGIC Proposal Submission System (MPSS).
Performance of the MAGIC Telescopes
The performance of the MAGIC telescopes during regular dark-time observations is reported in full detail in
Aleksic et al 2016,
while the performance of MAGIC during moon-light is reported in
Ahnen et al 2017.
The main performance plots are reported
in this page,
and a few key numbers are given below:
- Sensitivity for point-like sources (<0.1 deg):
0.8% the flux of the Crab nebula above 0.2 TeV in 50 hours of observation (using Sigma Li&Ma 1983, and 3 background regions), which is about 5% the flux of the Crab nebula in 1 hour.
The numbers from the differential sensitivity plot can be retrieved from
this page.
- Sensitivity for extended sources (>0.1 deg):
the sensitivity of MAGIC reduces with the source extension approximately as sqrt((0.1deg)^2 + (Source_Radius)^2), and the analysis becomes difficult (yet not impossible) for extensions larger than 0.6 degrees radius.
- Analysis energy threshold:
~75 GeV x pow(cos(Zenith_Angle),-2.3) for a Crab-like spectrum.
We note that, for strong and/or steep sources, it is possible to measure gamma rays below such threshold, as shown in
Ahnen et al 2015a
and
Ahnen et al 2015b,
where spectra starting at 40-50 GeV are reported.
- Energy resolution: about 20% per incoming gamma ray.
- Angular resolution: better than 0.1 deg per incoming gamma ray.
MAGIC PROPOSAL TOOLS
Source Visibility
The visibility of the source from the MAGIC site can be evaluated with
this custom-made source visibility tool.
Other publicly available visibility tools can be found at the
TeV Catalog and
Isaac Newton group of telescopes.
Source Detectability
A macro to evaluate the ability of the MAGIC telescopes to detect a gamma-ray source is available.
The macro takes a given spectral shape and, using the published MAGIC performance described above, estimates what kind of signal can be expected after a given amount of observation time.
The spectral shape and the amount of time for the observation is set inside the macro (see basic settings inside the macro).
Two versions are available: ROOT-based and Python-based. For detailed description and usage see the header of the files.
ROOT version:
mss.cpp
EBL model file:
ebl_tau.txt
Python version:
mss.py
In case you would like to use the results of this macro in a scientific publication, we would like to ask to cite Aleksic, J., et al., 2016, Astroparticle Physics, 72, 76 , which is the publication reporting the performance of the MAGIC telescopes.
Energy Threshold and Sky Brightness
The energy threshold depends primarily on the source zenith angle and on the level of sky brightness.
A calculator to compute the energy threshold for the different sky brightness conditions and zenith angles is available at
this web page.
Each target listed in the proposal must contain a maximum level of sky brightness:
the calculator will help you to evaluate the best limits on the sky brightness for your proposal.