I am pleased to invite you to respond to the 4th “Announcement of Opportunity” by submitting proposals for observations to be performed with the Insight-HXMT satellite. The Insight-HXMT Cycle 4 guest observation program is open completely to the whole international scientific community.
Insight-HXMT is China's first X-ray astronomy satellite. It was launched on 15th June 2017 and is currently in service smoothly (Zhang et al. 2020a). There are three main payloads onboard Insight-HXMT, the high energy X-ray telescope (20–250 keV, 5100 cm2) (Liu et al. 2020), the medium energy X-ray telescope (8–35 keV, 952 cm2) (Cao et al. 2020), and the low energy X-ray telescope (1–12 keV, 384 cm2) (Chen et al. 2020). The main scientific objectives of Insight-HXMT are:
(1) to scan the Galactic Plane to find new transient sources and to monitor the known variable sources;
(2) to observe X-ray binaries to study the dynamics and emission mechanism in strong gravitational or magnetic fields;
(3) to monitor and study Gamma-Ray Bursts (GRBs) and Gravitational Wave Electromagnetic counterparts (GWEM).
The Insight-HXMT Data Analysis Software (HXMTDAS, V2.04) and the CALDB have been frequently updated and the latest version (V2.04) has been released in November of 2020. In this software version, the method of spike removal and gain correction of HE have improved and the parameters of calibration and background have been updated. To facilitate the analysis of the GRB data, the Insight-HXMT GRB Data Analysis software (version: beta 1.4) has been released.
Users can download Level-1 data products from the Insight-HXMT official website (http://archive.hxmt.cn/proposal ). Members of core science team can apply for the core observation data within the proprietary period; PI of the guest observation can download the corresponding data; the data beyond the proprietary period or ad hoc ToO observation data are open to the public. Up to Dec 31, 2020, 1869 data product and 255 GRB data have been publicly released.
The key milestones for this announcements（UTC-8）:
Proposals Submissions Open time: Apr. 1, 2021
Proposals Due: Apr. 30, 2021
Announcement of accepted proposals: Jun. 30, 2021
Start time of the AO-04 Observations: Aug. 1, 2021
End time of the AO-04 Observations: Jul. 31, 2022
(1) Approximately 47 Ms of exposure time (also called effective observation time; for 50% observation efficiency, the actual observation time is two times longer) will be available in the observing period, in which the ratio for core proposals and guest proposals is 2:3, as shown in Table 1‑1. Up to 12 Ms of exposure time will be assigned for non-ToO observations (quiescent or persistent sources) and up to 35 Ms of exposure time would be assigned for ToO observations (transient sources, for whom the probability of the outbursts is approximately 10%). Accepted proposals will be awarded with priority A (30%), B (50%), and C (20%) targets, respectively, and priority C targets will be observed depending on the available time allocation. In addition, up to 2 Ms of exposure time will be reserved for the ad hoc observations, such as not pre-approved ToO or calibration observations.
Table 1‑1 The assignment of exposure time for different types of proposals.
Exposure time for core proposals
Exposure time for guest proposals
Total exposure time
4 (2.5 for galactic plane survey)
(2) The core proposals can ONLY be submitted by the core science group leaders, which will be reviewed and selected by the core science group. Data rights will be shared within the core science group members during the data proprietary period.
(3) The core science group members can submit the guest proposals, and follow the data policy of guest proposals.
(4) Proposals for the Galactic Plane scan, background observations and calibration observations are ONLY open to the core science groups now.
(5) Joint proposals are open to coordinated observations with other ground- or space-based observatories. If accepted, the proposers should secure the requested observations of other observatories before requesting trigger to Insight-HXMT and coordinate all observations.
(6) The data proprietary periods for this AO are one year for approved non-ToO observations and three months for approved ToO observations, if not specified and approved otherwise.
(7) “PhD Research Program”: Up to 20% of the data from the regular observations can be made for exclusive-use for PhD research. The PhD supervisors from the core science groups can apply for data protection in the proposals. If approved, the data will be protected during the proprietary periods.
(8) Data protection can also be applied to Ad Hoc ToO observations. If approved, the data proprietary period will be three months. Otherwise, Ad Hoc ToO data will be released immediately.
(9) Approved but not yet fully executed Priority A non-ToO observations from AO-3 will be moved to AO-4 automatically; the other approved but not yet fully executed AO-3 observations need to be re-proposed with scientific justifications.
AO-04 White Book of Insight-HXMT released：http://hxmten.ihep.ac.cn/doc/558.jhtml
Submit via the website (registration needed): http://proposal.ihep.ac.cn/proposal.jspx
Submit via the website (registration reuired): http://proposal.ihep.ac.cn/proposal.jspx
Guide for proposal submission: http://enghxmt.ihep.ac.cn/doc/170.jhtml
Observation time estimator: http://proposal.ihep.ac.cn/calc/calc.jsp
Target Visibility Predictor: http://proposal.ihep.ac.cn/TargetVisibilityPredictor/
Bright source warning tool: http://proposal.ihep.ac.cn/soft/soft2.jspx
Spectrum simulation tool: http://proposal.ihep.ac.cn/soft/user_spec_2020.zip
Instructions for proposal submission: http://enghxmt.ihep.ac.cn/doc/170.jhtml
Proposal forms download: http://enghxmt.ihep.ac.cn/doc/282.jhtml
List of Sources observed: http://hxmten.ihep.ac.cn/ObsSrcList.jhtml
Data Policy: http://enghxmt.ihep.ac.cn/policy/174.jhtml
Insight-HXMT core team composition and paper authorship rules: http://hxmten.ihep.ac.cn/policy/173.jhtml
Insight-HXMT publications: http://hxmten.ihep.ac.cn/papers.jhtml
I look forward to receiving your Insight-HXMT proposals.
Prof. Shuang-Nan Zhang, PI of Insight-HXMT
Insight-HXMT Science Center, Institute of High Energy Physics, the Chinese Academy of Sciences
Mar. 26, 2021
Questions, please mail to：
FAQ & Feedback: