ISSW from MPE A' Strong Sept 2001

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ISSW from MPE/ A. Strong/ Sept
2001 gensky source spectra, lines (Gaussian)
(formally part of OSIM) spiskycnv no essential
changes (formally part of OSIM spiskymax added
input/output source catalogues in ISDC format
Many formal deliveries mainly
updates to makefiles for changing ISDC platform
(templates, compiler), LINUX compatibility.
Exercised a lot on BLC data. utility'
programs (not formally delivered but should be)
spidisplay tool for displaying detector spectra
output from spihist spisumhist tool to combine
BLC data in flexible ways, eg
to simulate dithering of multiple
sources spisimprep convenient simulation of
large-scale surveys
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ISDC Observation Simulator
OSIM OSIM distributed publicly for AO-1, but
without SPI (just IBIS, JEMX) Important to
include SPI in future. SPI components for OSIM
gensky, spiskycnv to generate 'spihist output',
analyse with standard ISSW spiskymax, spiros All
these components have been delivered and accepted
at ISDC they just need to be integrated in OSIM,
with user manuals etc. OSIM also requesting extra
features like input from source
catalogues to gensky (not yet done) for
compatibility with IBIS, JEMX spiskymax now
handles catalogues as requested for OSIM OSIM
meeting 18th July at ISDC (AS attended) os_pdefgen
(pointing generator) is main useful tool for
SPI Simulation tools within ISDC system are very
important to maintain, even after we have BLC
data !
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spisimprep ISDC
pipeline impractical for large-scale survey
simulations with 1000 pointings (eg GCDE)
since creates directory structure for all
pointings, very large and time-consuming. Simulat
ions only need a subset of this data, only good
time intervals GTI, livetimes DTI are
dependent on ISDC pipeline, and spisimprep fills
in the gap os_pdefgen -gt attitude file gensky
-gt input skymap, energy bounds spisimprep -gt
GTI, DTI spiback -gt background
model spiskycnv -gt binned events spiskymax -gt
output skymap Allows very
efficient simulation studies
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200 - 400 keV continuum simulation 231 pointings
llt30o, blt20o, 2.3 106 sec
Singles doubles triples, IRF from GSFC
ISDC OSIM SPI issw os_pdefgen - gensky -
spisimprep - spiback - spiskycnv - spiskymax
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Simulation of actual GCDE with non-uniform
b-exposure will require an additional tool or
extension of os_pdefgen.
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IBAS SPI FOV Burst
Detection GRB-in-FOV detection foreseen as part
of ISDC IBAS system IBIS has working system
(Sandro Mereghetti) SPI-ACS burst detection
delivered (Nikolas Arendt, MPE) Requirement use
Real-Time Telemetry (RTTM) to locate GRB within
1 minute to issue trigger as input to IBAS Alert
Generation Initiative by MPE, will be
presented by Andreas von Kienlin.
ADD Version 1 produced
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IBAS SPI FOV Burst
Detection Proposal Split development into
interface with RTTM data aquisition via ISDC
routines, data selection and integration, as
input to detection algorithm Issue of trigger to
IBAS. Multithreaded (as SPI-ACS) for different
integration times,energies etc detection
algorithm detect GRB using detector counts fast
and reliable precomputed response for
predetermined energy range(s) (almost) no
background
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IBAS SPI FOV Burst
Detection interface with RTTM MPE
knowhow from SPI-ACS detection algorithm Bham
(PC) spiros, source detection expertise
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AS provided the following draft input
for the issue 2.0 of the IBAS ADD (can be updated
since issue will be in August). Section 4.4
Title GRB searching SPI Field of View Imaging
data SPI FOV analysis can be based closely on
that of IBIS for the data aquisition and message
generation aspects. The burst detection algorithm
itself should be developed independent from this,
taking account of the constraints imposed by the
limited data and fast processing. The data
aquisition principle will be to accumulate
event data directly from the telemetry as in the
IBIS case the only information required is time,
Detector ID, and energy channel. Only singles
events are required. This is sufficient to do
burst imaging in the instrument system. If a
burst is detected and its position in
the instrument system determined, the sky
coordinates can be computed subsequently from the
pointing information. The energy channel is
used to perform a basic energy selection, but an
accurate channel-to-energy calibration is not
required. The response will be pre-computed for
the standard energy channel selections. The data
will be accumulated for a time determined by the
parameter table and the burst search
performed. This is repeated at least at the 8
second rate of arrival of new data. However the
accumulation time can be longer or shorter than
this interval several accumulation times can be
run in parallel to optimize detection of long and
short bursts. The parameters should be
as similar as possible to those for IBIS. They
include accumulation time, significance level,
energy channel range.
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Timing for pulsar studies
Barycentrization ISDC routine will exist,
but need tool to use it. Analysis ISDC will
provide only xronos (HEASARC), no additional
development of a timing package. xronos
provides epoch-folding, power spectra etc. events
in ASCII -gt xronos FITS -gt interface required

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S. Paltani For ISDC library dal3aux Adapted
the code used for XTE and Chandra. The only
functionality is the transformation for a list
of photons from OBT or TT to TDB or TCB. int
DAL3AUXconvertBarycent(dal_element InputDS,
int NumTimes,
OBTime OBTtimes,
double RA,
double DEC,
BarySys TimeSys,
double BaryTimes,
int current_status) (BarySys
enum TDB, TCB ). If OBTtimesNULL, the
function assumes that TT times are found in
BaryTimes, and barycentric correction is done in
place. Need to convert the DE200 ephemeris file
to the ISDC standard Note that DE405 will not be
supported, as ESA sticks to FK5. Unfortunately,
it will be extremely difficult to test before
launch. It's quite probable that there will be
tools built around this function, but what is
needed need be discussed by the ISDC science team
(with very welcome inputs from ISDAG).
Barycentrization
Orbit information Time correlation
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Model fitting for diffuse
emission ADD started ..... but following is from
last ISDAG meeting Intend to start on this as
soon as BLC analysis complete' examples fitting
26Al to free-free .... fitting diffuse
continuum to HICO.... Is best method to get
spectra of diffuse emission. Complementary to
imaging. need general algorithm to fit data to
multiple components using full response
information s/w has much in common with imaging
(response/ convolution/background) so can reuse
software components.
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Model fitting for diffuse emission spidiffit'
Input SPI data components maps (as FITS
files) background specification (as for
imaging) specification of fitting parameters
Output fitting parameters with error
estimates resulting model skymap Development Can
base approach on existing COMPTEL codes like
difcor, diffit, and existing SPI imaging ISSW