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Following the PV phase, XRISM will enter the General Observer (GO) phase, which it will remain in for the lifetime of the mission, with annual Announcements of Opportunity (AO) released simultaneously by JAXA, NASA, and ESA. The institutional affiliation of the proposer determines which agency they should propose to. Persons at Japanese institutions should submit to the JAXA solicitation; those at US or Canadian institutions should submit to the NASA solicitation; and those with affiliations in ESA member and cooperating states should submit to the ESA solicitation. Persons with affiliations outside Japan, the US, Canada, or an ESA member state should submit to the JAXA solicitation, which reserves some time for such international proposals.
The data rights policy for XRISM is similar to previous missions. The normal exclusive use period for GO data is one year. This period may be waived if desired by proposers, but may not be extended.
The details of the AO are described more fully in the Call for Proposals (CfP). As with previous missions, proposals will be received by the relevant agency and evaluated by subject matter experts organized into review panels that make up the Time Allocation Committee.
Accepted targets will be classified into three categories: A, B, or C. Priority A and B targets are guaranteed to be observed, with A targets receiving a higher priority for observation scheduling. Priority C targets will be used as fillers when there are gaps in the schedule. Priority A and B targets that have not been completed by the end of an observing cycle are carried over into the next cycle. Priority C observations that are not observed during that observing cycle are not carried over. The goal of the target selection process is to produce a combined list of targets representing approximately 140 percent of the available observing time, split among A (50 percent), B (40 percent) and C (50 percent) priority observations.
During Cycle 1, category A and B targets will be considered complete if 90% (for A targets) or 70% (for B targets) of the proposed time is obtained on the source. In general, supplementary observations will be performed for A or B targets that do not meet the completion criteria, although it may not always be possible in case of time critical observations.
During the GO phase, data from calibration and TOOs requested outside the proposal process (see below) will not be considered proprietary and will not have an exclusive use period.
TOO proposals are allowed for XRISM through the normal proposal process, although they must be ranked as Priority A to be accepted. Proposals with TOOs should not be mixed with non-TOO targets. TOO proposals are allowed for short-lived events in known objects, the timing of which is uncertain. The trigger criteria must be explicit and quantifiable, and stated in detail in the proposal text; a brief summary should appear in the “Remarks” section of the target form. In addition, TOO proposals must provide an estimated probability of a successful trigger during the AO period. It is the PI's responsibility to notify the XRISM project when the criteria are met. Generic TOOs without a specific target (such as “a nearby supernova”) will not be accepted in Cycle 1. The number of targets in TOO proposals should not exceed 10. These policies are subject to change in future cycles.
The Solar panels on the XRISM satellite are fixed. This places a
restriction on the pointing direction with respect to the
satellite-Sun line: the Sun angle constraint during Cycle 1 is
60–120 degrees. This means that at any given time of the year, only
a swath of the sky 60 degrees wide is accessible for astronomical
observations, and thus most celestial sources are available for
observations for about 60 days every 6 months. If a specific
observing date or a coordinated observation with other missions is
required, the proposer must first determine if the observation is
possible. This can be done using the “Viewing” tool on the
HEASARC website:
https://heasarc.gsfc.nasa.gov/cgi-bin/Tools/viewing/viewing.pl
Long (
1 day) observations are the norm for XRISM. A large number of
short observations is an inefficient use of the satellite because of
the unusable time during slews and attitude settling. The pointing is
expected to be accurate to 0.3
and can be reconstructed to
better than 0.2, except during the initial settling period of
up to 10 minutes. Moreover, there is a limit on the number of slews
that can be uploaded to XRISM. For these reasons, a minimum exposure
time of 10 ks has been set for all proposed observations. For Cycle 1, observations will be limited to 300 ks per pointing with the total not to exceed 600 ks per proposal.
Contiguous observations, i.e., observations not disrupted by the observation of another target, are generally guaranteed up to exposures of not more than 100 ks. This limitation is due to moon light constraints for the star trackers' field of view, conflicts with other time critical observations, and other operational/planning difficulties. While the operation team does accept requests for uninterrupted observations longer than the 100 ks, these are conducted on a best-effort basis.
Even during shorter pointed observations, there will typically be
interruptions due to the location of XRISM in a low Earth orbit:
Normally, a target will be occulted by the Earth for 
30 minutes
every satellite orbit. In addition, XRISM will pass through the South
Atlantic Anomaly (SAA) during parts of 5 or 6 orbits every day. Due
to the harsh radiation environment of the SAA, scientific observation
is not possible during SAA passages. There are other variations in the
particle background, depending primarily on the Cut-Off Rigidity
(COR)3.1. Please check the XRISM
website for the most up-to-date
suggestions to reduce times of high background while maximizing the
science.
There are also orbital constraints on the orientation of the projected Resolve and Xtend FOV on the sky. Since both are approximately square, specific roll angle is not expected to be a common requirement. However, if a specific roll angle is scientifically advantageous, the proposer must first determine if it is allowed. Interested proposers are directed to the XRISM GOF web site for details. Then the required roll range can be entered on the RPS proposal form. For objects close to the ecliptic poles it is possible to arrange for any roll angle by scheduling observations at a specific time, but for those located close to the ecliptic, Resolve and Xtend will project on the sky in a nearly fixed orientation. Note that any roll constraint will make a proposal time critical.
It is possible to specify the time of observations (time critical, or TC, observations) in order to observe during specific phases or for simultaneous observations. Monitoring observations (repeated observations with a specified interval) or roll-angle constrained observations are also considered time critical, and must be so flagged on the proposal form. The total accepted time of TC and TOO proposals will be restricted; the numerical limit will be evaluated based on experiences but may be of order 15% of the total observation, and proposers should justify their requirements carefully.
Overall the proposers are strongly urged to provide the most accurate information possible. All information that is indispensable for operation planning should be provided on the electronic forms. The PIs are advised to utilize the “Remarks” area if they have detailed requests which cannot be expressed with the check boxes/pull-down menus.
After the XRISM proposal deadline, there will be three independent
proposal reviews for the NASA, JAXA, and ESA proposal solicitations. Each review
will create a target list from the proposed observations, ranking the
accepted targets as category A, B, or C. Only category A and B targets
are guaranteed to be observed. As stated above, TOOs and time critical
observations are only accepted within some limit (approximately 15% of the total time) –
however, the project will review this limit before the final target selection is made. Category C
targets will be observed as time permits. An international merging
committee will collate the three target lists and produce a single,
unified list. Overlaps among targets accepted by multiple agencies will be
resolved, either by merging the investigations (if both parties are
willing) or by choosing one. In the latter process, the priority given
by the national reviews, as well as the lengths of the accepted
observations, will be considered. The final target list will be 
% oversubscribed. Category A targets will have
50% of the available time, category B 40%, and category C 50%.
The Cycle 1 allocation of GO time among the mission partners is 48% for Japanese investigations (including 4% for international proposals), 44% for US investigations (including Canada), and 8% for ESA investigations.
Even though observations are scheduled to acquire roughly the approved exposure time and although this will usually be achieved with XRISM, occasional losses of usable observation time are inevitable. As mentioned above, Category A observations will be deemed complete when they have received at least 90% of the approved time. Note that this will be judged based on the good time intervals of the cleaned Resolve event files after the standard screening. Additional observations will be scheduled automatically for those non-time-critical targets the observations of which are considered incomplete by the project scientist at ISAS. In the case of time-critical observations which are incomplete or unusable, it will be the PI's responsibility to determine the best course of action.
Each PI will be assigned a contact scientist, either at ISAS or the NASA XRISM GOF, who will work with the PI to assure the maximum science return. This will include double-checking coordinates, count rates and finalizing configurations (nominal pointing, modes, etc.). It is important to note that once an observation has been scheduled, any delay in responding to questions from the contact scientist may result in targets being removed from the schedule.
Once the observation has been completed, the data will be promptly run through the processing pipeline and put into both the US and Japanese archives in encrypted form. The PI will be sent the decryption key, along with instructions on how to download and decrypt the data.
With the exception of the code that converts raw binary telemetry into FITS format files, all XRISM software is written as FTOOLS and distributed through the XRISM team at ISAS/JAXA and the NASA/GSFC HEASARC. This includes the tools used in the processing. All calibration files are distributed through the HEASARC caldb (calibration database) system. This enables users to apply any calibration updates themselves. The XRISM team at ISAS and the NASA XRISM GOF provide additional FTOOLS that may be necessary or desirable for analyzing XRISM data. The use of other software packages will only be supported at a lower priority level.