Detailed Design of the Science Operations for the XRISM mission

As described in Section 1, the goal of science operations is to enhance or maximize the scientific outputs of the mission. In science missions, the activities required of science operations can be divided into the following four categories.

SO1

Guest Observer (GO) program and data distribution

SO2

Distribution of analysis software and calibration database

SO3

GO supporting activities

SO4

Performance verification and optimization (PVO) activities

Many lessons were learned from the science operations in the series of Japanese X-ray satellites, and although some of them require no changes, others need to be addressed before the next mission. Table 1 summarizes the relations among lessons learned from the Advanced Satellite for Cosmology and Astrophysics (ASCA[7]), Suzaku[8], and Hitomi[2] missions, the details of which are described in Sections 2.2, 2.3, and 2.4 below. Positive and negative lessons are marked by + and - identifiers, respectively. Historically, attempts were made to address negative lessons in the next mission. However, this sometimes created another negative situation, which then needed to be solved in a subsequent mission. All of the lessons learned from past X-ray missions were considered by XRISM Science Operations, which are also shown in Table 1 and summarized in Section 2.5 below.

The ASCA mission was the fourth in the series of Japanese X-ray satellites [7] and was launched in 1993 carrying a Gas Imaging Spectrometer and Solid-state Imaging Spectrometer X-ray CCD cameras to observe astrophysical objects in the 0.5–10 keV band. The science operations activities as a public observatory were well established in almost the first collaboration between the Institute of Space and Astronautical Science (ISAS) at current JAXA and NASA/GSFC in the GO program (1a-ASCA⁺) and the distribution of observation data (1b-ASCA⁺), analysis software (2a-ASCA⁺), GO support (3a-ASCA⁺), international collaboration (4a-ASCA⁺), and calibration of instruments (4b-ASCA⁺), but there were also two negative items (2b-ASCA^- and 3b-ASCA^-). The successful parts of ASCA are summarized below.

1a-ASCA⁺:

The GO program worked well both in Japan and the US. GOs were able to submit their proposals to agencies, which were reviewed by the scientists and selected based on priorities, and information regarding the approved targets were used by mission operations in Japan. The basic procedures of the GO program were established.

1b-ASCA⁺:

All data products were well managed and distributed to GOs. The backbone of the procedure for processing and archiving observation data was established.

2a-ASCA⁺:

The core algorithms in the analysis software were well verified via on-ground calibration measurements before launch by instrument teams (ITs). Analysis tools using these algorithms and the calibration database were delivered to GOs. The concept was established in this mission.

3a-ASCA⁺:

As a part of the GO program, user support activities were established.

4a-ASCA⁺:

Collaboration between Japan and US was established on the ASCA science operations and was well organized especially on the development of the public software and the calibration database.

4b-ASCA⁺:

The instrument team members in Japan performed ground calibrations while scientists both in Japan and US performed continuous in-orbit calibrations, which delivered good calibration accuracy.

However, the following items can be regarded as negative lessons provided by this past mission.

2b-ASCA^-:

The instrument team members developed their own tools for analyzing the ground calibration data, which sometimes provide better results than the public analysis software released as part of item 2a-ASCA⁺ in the early GO phase. Since these tools were not initially made public, they became referred to as ”animal software” because of the unfairness of the analyses from the viewpoint of a public observatory, although this unfair situation was resolved in the final version of the products.

3b-ASCA^-:

GO support was provided only in the US by the US ASCA Guest Observer Facility (GOF), but not in Japan, although instrument teams in Japan provided deep support for the GOF activity. The interface to GOs existed only in the US.

The Suzaku mission was the fifth in the series of the Japanese X-ray satellites in collaboration between JAXA and NASA [8], and was launched in 2005 carrying the High-throughput X-ray Telescope, X-ray Imaging Spectrometer CCD cameras, and non-imaging Hard X-ray Detector. The science operations members of Suzaku tried to utilize the positive lessons from ASCA (i.e., on the GO program and data distribution 1a-ASCA⁺ and 1b-ASCA⁺, the software development 2a-ASCA⁺, the GO support 3a-ASCA⁺, and the PVO activities 4a-ASCA⁺ and 4b-ASCA⁺) and fix the negative situations (2b-ASCA^- and 3b-ASCA^-). They successfully fixed these using 2ab-Suzaku⁺ and 3b-Suzaku⁺, respectively, which are summarized below.

2ab-Suzaku⁺:

In order to keep the positive situation 2a-ASCA⁺ and solve negative situation 2b-ASCA^- (i.e., avoiding animal software), the public tools and tools for ground calibration measurements were designed to have the core algorithms for calculating variables such as time, pulse-height invariant (PI[9]), and grade, shared as software libraries. The instrument team members developed and verified these core libraries via hardware development, and the same libraries were smoothly exported into public tools that could be used by the GOs. Therefore, the public tools were well verified and well calibrated.

3b-Suzaku⁺:

In order to improve situation 3b-ASCA^-, a Suzaku Help Desk in Japan (RIKEN)[10] were operated in addition to the Suzaku GOF in the US. Since several members of the Suzaku Help Desk also belong to the instrument teams in Japan, these two bodies had a strong potential for solving questions from GOs very quickly because of their tight connection to the operation team and developers of instruments.

In addition, starting from Suzaku, communication was established with other X-ray missions in terms of calibration activities (keeping 4b-ASCA⁺), as indicated as 4c-Suzaku⁺ below.

4c-Suzaku⁺:

The Suzaku instrument members participated from the beginning in cross-calibration activities in the International Astrophysical Consortium for High Energy Calibration (IACHEC) [11].

However, the following two negative points related to 2ab-Suzaku⁺ and 3b-Suzaku⁺ arose in the Suzaku Science Operations, and were left as open issues for the next mission (Hitomi).

2c-Suzaku^-:

Software development by the instrument teams in 2ab-Suzaku⁺ caused a) unexpected software freezes and b) delays in the delivery schedule, because a) not all the instrument members were experts on programming, and b) the first priority of the instrument teams was the delivery and maintenance of the detector itself, with software development having a lower priority.

3c-Suzaku^-:

The members of the Suzaku Help Desk in Japan (3b-Suzaku⁺) were not appointed by the agency and had no special data-access permission. Therefore, the tasks were performed on a best-effort basis and sometimes activity stopped because of other business.

The Hitomi mission was the sixth in the series of Japanese X-ray satellites developed at JAXA in collaboration with NASA and Japanese and Canadian institutions with contribution from the ESA [2], and carried an micro X-ray calorimeter array and X-ray CCD cameras on the focal plane of X-ray mirrors, as well as hard X-ray instruments with hard X-ray mirrors and a soft gamma-ray detector. The satellite was successfully launched in February 2016, but contact with the spacecraft was lost in March 2016 owing to problems in the bus system before the performance verification (PV) phase. Therefore, most of the science operations after launch were not activated, as indicated by 1a-Hitomi^±, 3-Hitomi^±, and 4-Hitomi^± below.

1a-Hitomi^±:

Opportunity for calling for GO proposals was canceled, although the distribution of the in-orbit data was completed (keeping 1b-ASCA⁺).

3-Hitomi^±:

GO support helpdesks were prepared but not activated.

4b-Hitomi^±:

Calibration of instruments was performed on the ground and partially in orbit during the commissioning phase, and the results were released in the calibration database.

In the science operations of Hitomi, positive lessons from ASCA and Suzaku were kept in the activities under the above situations, including participation in the IACHEC (4c-Suzaku⁺). In parallel, the science operations members tried to solve negative item 2c-Suzaku^- (leaving 3c-Suzaku^- open when the mission terminated), and it was solved as 2c-Hitomi⁺ with 2d-Hitomi^- left as an open issue as shown below.

2c-Hitomi⁺:

In order to avoid 2c-Suzaku^- (unexpected software freeze and schedule delay), a specific team was defined for the development of software and the calibration database. The team was the Hitomi software and calibration team (SCT) and was independent from the instrument teams and consisted of scientists and programmers. As a result, there were no delays in the schedule of software preparation and no delay in the release of tools and the calibration database. The products were well calibrated using instrument-specific methods[12, 13, 14, 15, 16, 17, 18, 19, 20, 21], because all the algorithms were imported into the analysis software and the latest calibration information was quickly released in the database[5].

2d-Hitomi^-:

In order to achieve 2c-Hitomi⁺, there were many interactions among the software and calibration team, instrument teams, and operation teams, which were spread across multiple agencies. Therefore, many more tasks than expected were required in order to manage tasks for science operations such as the schedule, manpower of activities, and interfaces.

In summary, from the lessons learned from ASCA, Suzaku, and Hitomi missions, two items labeled 2d-Hitomi^- (team management issues) and 3c-Suzaku^- (data access rights in users support) remain as open items for the XRISM Science Operations, with the remaining items recommended to remain unchanged. The two items are related to the management of manpower and the preparation of science operations before launch.

Considering the recommendations from lessons learned from past X-ray missions (Section 2), the key points of the XRISM Operations Concept can be summarized into the following three items.

1. OC01

   Clear division between spacecraft operations (hereafter, ”mission operations”) and science operations is required so that the scientists can concentrate on science operations.

2. OC02

   The plans for the operations (both mission and science operations), including the team structure and interfaces, should be defined in an early phase before launch. Similarly, training and actual operations should start before launch.

3. OC03

   All members of the operations (both mission and science operations) should be appointed by the agencies, and all activities, except for PVO activities (see Section 2.1), should be performed as well-defined tasks with clear due dates, that continue to work until the end of the mission.

In operations concept OC01, operations tasks that require scientific decisions from the viewpoints of scientists are all assigned as XRISM Science Operations, and all other tasks are assigned as XRISM Mission Operations. For example, the weekly negotiation of contact passes of ground stations, generation of daily operation commands, execution of the spacecraft simulator, down-link-and-command operations at ground stations, and checking the house-keeping telemetries from the spacecraft in real-time and off-line are assigned as tasks for mission operations. On the other hand, the handling of proposals from GOs, scientific scheduling of astrophysical objects, quick-look checks of science telemetries, instrument calibration activities¹¹1However, the calibration activities were shared among XRISM-internal groups, as described later in Section 5., and the management of daily data process and archive operations and user support activities are considered tasks for science operations.

We defined individual teams for performing XRISM Mission Operations and XRISM Science Operations separately, which are called the Mission Operations Team (MOT) and Science Operations Team (SOT), respectively. Following the lessons of 2c-Hitomi⁺, these teams also need to be independent from the instrument teams. In addition, we defined the Science Management Office (SMO) to manage the overall XRISM Science Operations for deciding items regarding science operations. For example, the SMO handles activities such as calling for, reviewing, and selecting GO proposals, and approving targets for director time-of-opportunity (ToO) observations.

In operations concept OC02, the operation phases of the XRISM are defined as follows.

1. 1.

   Before Proto-Flight Test (PFT) Phase

2. 2.

   PFT Phase

3. 3.

   Launch Preparation Phase & Launch Phase

4. 4.

   Initial Phase, which consists of the Critical Operations Period and Commissioning Period

5. 5.

   Nominal Operations Phase, which consists of the Initial-Calibration and Performance-Verification (PV) Period and Nominal Observation Period

6. 6.

   Latter Phase, which consists of the Latter Observation Period and Completion of Operations

Based on concept C02, the phase in which science operations starts should be the 2) PFT Phase, not the 5) Nominal Operations Phase after launch. In other words, preparation of the mission and science operations should be completed before the PFT Phase on the ground, and the MOT and SOT shall start from the PFT Phase. Therefore, we define the Mission Operations Planning Team (MOPT) for preparing the mission and science operations (e.g., construction of the detailed operations plan, preparation of the OTs and ground system), which is active from the 1) Before PFT Phase.

According to operations concept OC03, all members of the MOT and SOT should be appointed by the agencies (JAXA or NASA), and work on well-defined tasks under a managed schedule until the end of the mission, although members of the MOPT may be non-appointed members from universities as developers of tools in the Before PFT Phase. The SOT members consist of not only leader(s) and senior scientists, but also young scientists, referred to as Duty Scientists, who perform the actual XRISM Science Operations and are appointed by the agencies. In our concept, the tasks of the Duty Scientists should be defined such as to provide a good career path for young scientists. Note that the concept of the Duty Scientists is applied only on the science operations center in Japan as described in the next section 4.

In addition to the SOT, MOT, and SMO described in Section 3, the XRISM team consists of the instrument teams, namely, the Resolve and Xtend teams, and the In-flight Calibration Planning Team (IFCP)[22], which provides the detailed plans for in-orbit calibration observations before launch. Interactions between these subgroups after the PFT Phase (Section 3.3) are summarized in Figure 1.

The SOT is directed by the Project Manager (PM), and works with the SMO, which provides recommendations and specifications for science operations as established in the concept study in Section 3. The SOT does not communicate directly with the Science Advisory Committee, but rather through the SMO. The SOT communicates with the MOT regarding tasks such as the planning of spacecraft operation, verification of telemetry data, and reports. Several tasks such as in-orbit calibration observations and instrument performance monitoring are performed in collaboration with the Resolve, Xtend, and IFCP teams. The SOT communicates with GOs directly regarding the acceptance of proposals and user support activities. Communications with other observatories (i.e., X-ray missions and/or observatories in other wavelengths), negotiations for in-orbit calibration campaigns, and/or multi-wavelength scientific programs are handled by the SMO, and communications on actual observation plans/schedules are handled by the SOT. Similarly, decisions regarding press releases of scientific outputs or mission status are made by the SMO, and the actual work of the publications is done by the SOT members under the direction of the SMO.

The calibration activities of payload instruments consist of many steps, and the task divisions among the SOT, instrument teams, and IFCP team are defined as Table 2.

The XRISM Science Operations are covered by JAXA, NASA, and the ESA. Since tight collaboration between JAXA and NASA is required for preparation and maintenance of the data distribution (SO1 in Section 2.1) and analysis software and the calibration database (SO2 in Section 2.1), the SOT is designed to operate at the Science Operations Center (SOC) at JAXA and the Science Data Center (SDC)[23] at NASA, as shown in Figure 2. Each center is made up of leads, scientists, and software engineers. In the SDC, the Product Development Lead and the Science Lead direct the SDC internal groups, namely, the Data Center Team, Guest Observer Facility, and User Support Group. The SOC is activated after the PFT Test Phase (see Section 3.3), and the SOC Lead directs SOC members, such as the Duty Scientists defined in Section 3.3 and Supporting Scientists from the MOPT, after the PFT Phase. Before launch, the science part of the MOPT is also under the direction of the SOC Lead, and consists of three groups: the Process and Plan Group, the PVO Group, and the User Support Group. In addition, the ESA operates the European Space Astronomy Center (ESAC) from the Before-PFT Phase and communicates with the SOC and SDC for the science operations in Europe.

The task divisions among the three centers in JAXA, NASA, and ESA are defined in Table 3, summarized into four categories (SO1, SO2, SO3, and SO4 in Section 2.1). The details of these tasks are described in the next Section 5.

All specifications of the overall science operations are handled by the SMO, and therefore, the Mission Principal Investigator (PI) and co-PI (JAXA/NASA), Project Scientists (JAXA/NASA/ESA), Deputy Project Scientists (JAXA/NASA/ESA), and all the leaders of the internal subgroups (SOT and Resolve and Xtend teams) except for the MOT and IFCP team in Figure 1 belong to the SMO Committee in the Nominal Operations Phase, as shown in Figure 3. The Project Managers both in JAXA and NASA also belong to the SMO as ex officio. Before launch, leaders of the IFCP team, chairs of the science categories, which are active in the selection of the PV targets, and chairs of subgroups for specific topics such as atomic physics also participate in the SMO.

Following concept C03 in Section 3.1, the members marked by $\largestar$ in Figure 3 are appointed by the agencies, namely, JAXA or NASA (or the ESA). Within the SOT, the SOC plans to have eight Duty Scientists (see Section 3.3), as well as Support Scientists from the MOPT (Section 3.3) and/or JAXA academic positions to help the Duty Scientists, as described in Section 4.2. In the SDC, more than seven staff scientists and more than four software engineers will perform the science operations at NASA. All members of the SOC and SDC are appointed by JAXA and NASA, respectively, in the Nominal Operations Phase.

In the science operations performed by the SOT, SOT members have access to all of the telemetry items including scientific properties in order to check the performance of the instruments and to make quick-look reports to GOs. These activities are limited to monitoring or checking of the instrument health and performance, and do not extend to performing scientific analyses of the scientific interests of scientists. The SOT members also check all the proposals approved by the SMO and their scientific justifications. While SOT members can access all the data and products to the extent that such access is required to perform their duties, they are required to maintain confidentiality of all scientific knowledge obtained in this context. The SOT members shall understand this data access policy in all of the science operations.

All the tasks for the XRISM Science Operations are defined in terms of the four types of science operations defined in Section 2.1 (i.e., SO1, SO2, SO3, and SO4) in Table 4, which can be categorized into the following three-step operation flow.

1. Step-1:

   Proposal and Planning Step (before observation)

2. Step-2:

   Telemetry Check and Data Processing and Archive Step (after daily spacecraft observation)

3. Step-3:

   User Support and PVO Step (after distribution of the observational data to GOs)

These steps are performed in parallel with observations, and are operated both by the SOT and MOT, with various timescales (once per year, monthly, weekly, daily, and continuous), as also shown in Table 4. The tasks for the SOC in Japan (see Table 3) are shared among the Duty Scientists and the SOT Scheduler (who works on planning as a contribution from SDC staying at SOC; Figures 2 and 3) evenly by week or month. For example, one Duty Scientist performs the first task, which is then performed by another Duty Scientist the following week.

Most of the tasks in Step-1 before observation are of Type SO1 (defined in Section 2.1), which can be divided into the following two categories. The details are as follows.

• •

  GO proposal support

  • –

    The SOT supports calls for proposals by the SMO and receives proposals from GOs. During proposal acceptance, the SOT supports GOs with preparation of proposals (SO3).

  • –

    After the review process, the SOT gets a prioritized approved target list from the SMO. In parallel, the in-orbit calibration objects are merged into the list. The SOT puts information regarding approved targets and calibration objects into the observation database and opens the list via the webpages of the researchers.

• •

  Observation planning

  • –

    After the SOT obtains the list of targets, the SOT Scheduler (defined in section 5.1) generates a long-term operation plan taking into account the spacecraft operational constraints.

  • –

    Using the long-term plan as a guide, the SOT generates a more detailed short-term observation schedule weekly and prepares the detailed plans for observations for the week.

  • –

    During preparation of the observation details, the SOT notifies the observation PI of the plan, and negotiates the hardware configuration with the instrument teams.

  • –

    In addition to the planned objects, the SOT handles ToO proposals from GOs. If the SMO approves a ToO proposal, the short-term operation plan is quickly updated and used for the spacecraft operations.

  • –

    Before spacecraft operations, the SOT acts as an interface to the MOT from SMO and GOs on scientific topics for the generation of operation commands to the spacecraft.

The tasks in Step-2 after observation are a mixture of Types SO1, SO2, and SO4 (Section 2.1), and can be divided into the following three categories. The details are as follows.

• •

  Telemetry check

  • –

    Telemetry from the spacecraft needs to be checked quickly after spacecraft operation. In order to quickly perform these telemetry checks before the official data processing for GOs, which takes about one or two weeks in total, a Quick-look Data Process (QLDP) is defined to generate products quickly. The QLDP simplifies the timing calibration, orbit determination, and attitude determination processes from the official data processing.

  • –

    The MOT executes the QLDP and performs the quick health checks of instruments using the housekeeping telemetry semi-automatically. This function checks every value of the attribute in the engineering housekeeping telemetry to verify the proper and safe operation of the observatory at all times. If the MOT find an anomalous telemetry for the spacecraft safety from this limit checks, they will respond immediately as an emergency operation. In any cases, the MOT reports the results to the SOT daily after the spacecraft operation.

  • –

    In addition to the engineering health checks by the MOT, further checks of the performance of payload instruments from a scientific viewpoint are also required for the SOT. The SOT uses the products from QLDP of not only the housekeeping telemetry but also the science telemetry, performs the pipeline-equivalent process to calculate data such as the time, coordinate, and energy information, and then checks the instrument performance.

• •

  Data Process

  • –

    After spacecraft operation, telemetry is converted into the FITS format[4] by the pre-pipeline (PPL) process, and then higher-level calculations, such as filling time, coordinate, and energy information (PI[9]), are performed by the pipeline (PL) process. (Note that the details of the PPL and PL are described later in Section 6.2.1.) The products of the PPL and PL are archived and distributed to GOs. Execution of the PPL and PL is performed by the MOT supported by the SOC and the SDC, respectively.

  • –

    The products of the PPL and PL are checked by the SOT before the distribution to GOs.

• •

  Archive

  • –

    The products of the PPL and PL checked by the SOT are archived both in JAXA and NASA archive centers, the Data ARchive and Transmission System (DARTS) and the High Energy Astrophysics Science Archive Research Center (HEASARC), respectively.

  • –

    When the products are archived, the SOT notifies the readiness to GOs.

The tasks in Step-3 after data distribution are of Types SO3 and SO4 (defined in Section 2.1), which can be divided into the following two categories. The details are as follows.

• •

  User Support

  • –

    The SOT prepares and operates webpages for GOs to provide information on GO proposals, operation schedules and logs, analysis documents, etc. Such researcher website for XRISM are prepared at the three agencies, JAXA, NASA, and ESA, separately but main contents are synchronized.

  • –

    The SOT operates the agency Help Desks for handling questions from GOs.

  • –

    The SOT prepares documents related to the data analyses of XRISM, such as analysis walkthrough, analysis manuals, and descriptions of instruments.

  • –

    Education and Public Outreach (EPO) activities are performed by other institutes in JAXA or NASA, and the SOT supports such activities for XRISM.

• •

  PVO Activities

  • –

    As defined in the task division of the calibration activities in Table 2, the SOT calibrates payload instruments regularly with the instrument teams using the in-orbit calibration targets or trend archive data (i.e., non-scientific data obtained for performance monitoring, such as data during earth occultation of normal operations).

  • –

    In addition to the daily performance checks in Step-2, the SOT also monitors the instrument performance monthly.

  • –

    The SOT enhances the instrument performance (such as improving the pointing accuracy and tuning of the good time interval) by checking short-/long-term trends and correlations between telemetry items and performance parameters. The output of such performance enhancement activities are implemented as an analysis thread or a new analysis tool, which is provided to GOs via the researcher website or the software archive.

  • –

    During the daily data checks in Step-2 (Table 4), the SOT carries out further analyses to search for possible new transient objects within the field of view of Xtend using the quick-look data products and the final products. If the SOT finds a transient and the SMO considers it worth reporting, the SOT posts a quick report to the Astronomers Telegram (ATEL, http://www.astronomerstelegram.org/) from quick-look data products, and updates the detailed information using the final products if necessary. This activity is performed during the Initial-Calibration and PV Period under the permission of the observation PI during the Nominal Observation Period.

In each operation phases defined in Section 3.3, the MOPT and SOT prepare and/or perform the science operations following the timeline shown in Table 5, respectively. Before the launch, on ground, the MOPT prepares the descriptions for science operations, such as the science operations plan, the manual for the science operations, and the detail design of the operation tools (OTs), etc, and develops and verifies the OTs in the before PFT phase, and then trains the SOT members in the PFT phase. The list of targets to be observed during the initial-calibration and PV period in the Nominal operations phase (Section 3.3) is released during this phase. The PV target list has been released on Febrary 15, 2021. After the launch of the satellite, the SOT supports the critical and commissioning operations by the MOT and ITs during the initial operations phase, prepares the data process of the first light object at the end of commissioning period, and, after that, performs the nominal operations in the Normal Operations Phase.

The tools and database required for the XRISM Science Operations by the steps (Section 5.1) are summarized in Table 6. The responsibilities for these tools/databases in the subgroups within the SOT are also shown. Among these 10 OTs, the proposal submission tools, planning tool, PL, calibration database, and analysis tools (OT01, OT02, OT06, OT07, and OT09, respectively) are developed by the SDC, and the details of these OTs are described in Loewenstein et. al. (2020)[23]. Hereafter, this paper describes the details of the observation database, QLDP, PPL, and archive quick-viewing tool (OT03, OT04, OT05, OT08) in Section 6.2 and the conversion tools for the researcher webpages (OT10) in Section 6.3.

Researcher webpages are required for communication with GOs for the user-support activities listed in Table 4, and are planned to be operated in three centers: SOC, SDC, and ESAC. In the first version, the following content is listed on the researcher webpages at SOC.

• •

  Top page, News and Announcements

• •

  About XRISM (XRISM documents, workshops, publication list, resources)

• •

  Proposer (GO proposal documents, response files, generic ToO request, approved target list)

• •

  Observers (short-term/long-term operation plan, spacecraft operation log)

• •

  Analysis (manual, link to archive web, link to download page for software/calibration database)

• •

  XRISM Help Desk (FAQ, proposal plan support, analysis questions, XRISM workshops)

• •

  Useful links (link to general public XRISM website, DARTS archive website, HEASARC website, ESAC website)

The MOPT prepares the web servers and the tools for filling the content of the pages of observation plan and spacecraft operation log semi-automatically. These tools are identified as OT10 in Table 6. The JAXA researcher webpage was opened on 1 November 2020 at https://xrism.isas.jaxa.jp/research/ and is used for announcements to GOs before launch and is to be activated on the science operations after launch.

In principle, all the PVO activities are performed by all the science members of the XRISM team before launch. The items for the MOPT to prepare for the science operations in orbit are the detailed procedure for opening these efforts to GOs via the XRISM software, calibration database, and the analysis method, which are already covered in Section 5.

In order to perform the four science operations tasks described in Section 5.4 and Table 4, the MOPT prepares the following items.

• •

  Calibration analyses
  As defined in Table 2, the in-orbit calibration items and procedures are prepared by the instrument teams, and the SOT also analyzes the plan to observe the in-orbit calibration observations with the instrument teams. Therefore, the MOPT prepares the training procedure for understanding the calibration items and procedures with the instrument team before launch.

• •

  Monthly performance check
  Daily and monthly checks of instrument performance require no special tools other than the standard analysis software. In this sense, the MOPT has no plan to prepare the tools before launch. If the MOPT identifies additional tools during the rehearsal of instrument operation on ground in the PFT Phase (Section 3.3), the MOPT will prepare the tools from this phase.

• •

  Development of analysis threads and tools
  All of the standard analysis will be performed using the public standard tools (OT08 in Table 6). For the monthly or daily performance checks, the SOT tries to study and identify new proprieties or behaviors of instruments which affect the instrument performance. If the SOT finds a way to enhance the instrument performance using these items, the SOT will implement the procedure as an analysis thread or prepare a new public tool using the newly found algorithm.

• •

  Xtend transient search
  As described in Section 5.4, the SOT carries out further analyses to search for possible new transient objects within the field of view of the Xtend and posts a quick report to the ATEL, under the permission of the observation PIs. The MOPT prepares the detailed procedure for this operation to obtain a quick response and the automatic search tool of transients.