September 1, 2006
Announcement of Opportunity (AO-2) of Suzaku
1. Overview
The Japanese-US X-ray Astronomy satellite Suzaku was launched by
ISAS/JAXA on 2005 July 10, and has since successfully carried out
astronomical observations using the 4 X-ray CCD cameras (XISs) and
Hard X-ray Detctor (HXD), although the X-Ray Spectrometer (XRS) is no
longer operational. Between 2005 September and 2006 March ("SWG phase"
- see below), observations were carried out for instrument calibration
and performance verification, which confirm the wide-bandpass,
high-sensitivity, moderate spectral resolution capabilities of Suzaku.
In 2006 April, we entered the 1-year international AO-1 phase of the
mission, performing observations based on proposals received from the
astronomical community world-wide. We plan to start AO-2 observations
in 2007 April, and hereby invite submission of observing proposals as
follows.
US based scientists should consult the parallel announcement at
http://astroe.gsfc.nasa.gov/
while scientists in ESA member countries should consult the version at
http://www.rssd.esa.int/Suzaku
Present version is applicable to scientists based in all other
countries.
2. Suzaku observatory
The Suzaku satellite carries four X-Ray Telescopes (XRTs) that
focus X-rays up to 12 keV with a high efficiency, each with an XIS
unit at its focus. The XIS has a high sensitivity particularly for
extended sources, as well as good spectral resolution, for soft X-rays
below 0.8 keV, a capability that is superior to those of Chandra and
XMM-Newton. At the same time, the HXD, though non-imaging, has
unprecedented sensitivity in the wide energy range up to several
hundred keV. The wide bandpass coverage with the XIS and the HXD is an
important characteristic of the Suzaku mission, so we invite observing
proposals that make strong use of their sensitivities. The details of
the instruments (Technical Description document), and a list of
targets that have been observed or will be observed within the SWG
(see below) time and AO-1 can be found at the
http://www.astro.isas.jaxa.jp/suzaku/
We plan to update the Technical Description document, as well as
planning tools, with latest information in early October; existing
versions should suffice for early planning of proposals, but may not
give accurate results when detailed simulations are performed.
3. Mission phases and time allocation
The Suzaku mission has been developed as a Japanese-US
collaboration, and the Science Working Group (SWG) that consist of
researchers involved in the development and operation oversees the
project overall. After the end of the SWG phase of the mission
(through 2006 March), normal observations during AO-1 are entirely
through open proposal process. Similarly, observing time during
international AO-2 (1 year period starting 2007 April) is open. This,
however, excludes the following categories.
- Observatory Time (4%) for satellite maintainance and related purposes
- Calibration time (3%) for routine calibration of instruments
- Director's Discretionary Time (5%) for any genuinely unpredictable events including gamma-ray bursts, and other important observations granted at the discretion of the mission director.
The remaining 88% of total time is available to proposers. This
will be divided into (1) 50% for Japanese observations; (2) 37.5% for
US observations; and (3) 12.5% for joint Japanese-US observations. The
joint time will be used if proposals were received for the same target
both in Japan and in the US, and if both PIs accept such merging (the
proposal form will have a check box for the PI to indicate yes or no).
This allocation is based on an ISAS-NASA agreement. Additionally,
within the "Japanese" allocation, 8% of the observing time is reserved
for proposals submitted to ESA as joint Japan-ESA observations, thus
the purely Japanese time is 42%. The total time available to Japan
researchers is 4923 ks, plus 1465 ks of joint time, assuming 37 ks of
good time per day and 360 days of operation per year. Proposals from
non-US, non-ESA countries will be accepted within the Japanese time up
to the ESA portion (938 ks).
4. Observing Constraints
Over 200 objects will have been observed with Suzaku during the SWG
and AO-1 peirods. A full listing can be found on the web.
http://www.astro.isas.ac.jp/suzaku/accept/
Observations of accepted priority A and B targets are guranteed,
while those of priority C targets and Targets of Opportunity (TOOs)
are not (see below for definitions of target priorities). Proposals
for targets already observed are allowed, but must include a
justification for an additional observation, such as a much longer
exposure, different pointing within an extended object, or different
observing window of a variable object. Proposers with an accepted C or
TOO targets must re-propose if they wish to ensure that their
observations are carried out (these targets are in principle open to
competition). It must be noted that if the C target is observed in
AO-1 with more than 70% of proposed time, it will not be observed in
AO-2. If not, it will be observed until total time become 70% of
proposed time of B proposal, while 90% for A proposal. In these cases,
data should be shared by authors of AO-1 and AO-2.
The length of the observation should be justified based on the
specific scientific objectives, preferably using simulations. However,
we set the minimum observing time at 10 ksec, considering the
efficiency of satellite operation. There is no upper limit to for the
observing time, but longer observations will naturally require
stronger scientific justifications.
It is possible to specify the time of observations (time critical
(TC) observations) to observe specific phases or for simultaneous
observations. The monitoring observations can be proposed with certain
interval. You also able to chose the roll angle of the optical system.
In all these cases, you have to put on the TC flag in the application
form.
Target of opportunity (TOO) proposals are allowed for short-lived
events on known objects whose timing is uncertain. The name and
coordinates of the object(s) as well as the triggering conditions must
be specified. We also require the estimated probability during AO-2 of
such an event, as well as its duration. Generic TOOs without a
specific target (such as "a nearby supernova") will not be
accepted. The number of targets listed in a reserved TOO proposal
should not exceed 5.
Any genuinely unpredictable events may be observed outside the
proposal process, as part of the 5% Director's Time. Data from such
observations will not have a proprietary period. Please make a contact
to us (following e-mail address) for these cases, except for gamma-ray
bursts.
Gamma-ray burst TOO observations will be planed by the Suzaku
science working group.
5. Review process and schedule
Researchers based in Japan, and non-US, non-ESA countries should
submit proposals to ISAS/JAXA. The deadline is 2006 December 1 at noon
JST for proposals. All proposals from Japan and other countries will
be reviewed in the same process in Japan. After the review in Japan
together with the ESA proposals, a Japan-US merging committee will be
convened in February, and the final observing program will be
published soon thereafter.
Accepted proposal will be classified into three
categories. Priority A targets will be preferentially observed during
the AO-2 period (2007 Apr to 2008 Mar). Priority B targets will be
scheduled in this period as far as possible, but may be carried over
to the following AOs. Priority C targets will be used as fillers when
there are gaps in the schedule. For the total available time T, we
will accept 0.5T, 0.4T, and 0.5T as As, Bs, and Cs (for a total
oversubscription by 40%). If the actual amounts of observatory,
calibration, and director's times add up to less than 12% that is set
aside, then the remainder will be used to observe additional C
targets.
TOOs and time critical observations will be accepted only as priority
A targets.
6. Data rights
Observers will have exclusive rights to the data for a 1 year
period after receipt of data, after processing. This, however, does
not apply to real time TOO observations and for Gamma-ray burst
data. We will deem an observation complete if 90% (for A targets) or
70% (for B targets) of the proposed time is obtained.