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HETE-II HETE-II CatalogueCatalogue
Filip MFilip Müünz, Elisabetta Maioranonz, Elisabetta Maiorano
and and Graziella Pizzichini Graziella Pizzichini
for HETE teamfor HETE team
Burst statistics in
gamma-ray detectorFrench Gamma-ray TelescopeFrench Gamma-ray Telescope (FREGATE): (FREGATE): 5-400 keV; ~5-400 keV; ~ππ FOVFOVno localizationno localization
position sensitive instrumentsWide-Field X-ray MonitorWide-Field X-ray Monitor (WXM): (WXM): 2-25 keV; ~5’-10’ localizations2-25 keV; ~5’-10’ localizationsSoft X-ray CamerasSoft X-ray Cameras (SXC): (SXC): 2-10 keV; ~40” 2-10 keV; ~40” localizationslocalizationssmall eff. surface / sensitivitysmall eff. surface / sensitivity
direct alert transmission through simple VHF stations along the equatorial trajectory
High Energy Transient Experiment – IIHigh Energy Transient Experiment – IIvery small scale mission
mass: 123 kgsize: 89 x 66 cm (launch size)
Pisa, May 2009
HETE-II GRB CatalogueHETE-II GRB Catalogue
Detector responseDetector response FREGATE
large FoV implies high background (with Earth occultation of sources due to fixed pointing )
WXM extension to lower energies
with complicated response matrix (1-D coded masks)
1292 GCN alerts 173 bursts
143 localized (110 within 1 hour)
Pisa, May 2009
GRB – SN connection (030329A)
HETE HighlightsHETE Highlights
HETE
X-ray (Chandra)
optical
first short burst OT (050709)
Pisa, May 2009
Catalog contentCatalog content
284 bursts
(some cancelled
later)
results of analysis
of different groups
more concerning
position
reconstruction
Pisa, May 2009
Checking the catalogueChecking the catalogue
correlation of different variables (160 entries) looking for outliers
Pisa, May 2009
GRB entryGRB entry
All links on one page to general catalogue to GCN notices to literature custom notes
Pisa, May 2009
Catalogue structureCatalogue structure Database (mySQL) with object
interface (and web replication ) Numerical Python, Django,
JQuery light-curve profiles in ASCII/FITS
procedures to load and subtract background
Burst (trigger info)
Alert (time of distribution)
Spectral fits
Band (X/gamma)
Peak (times,fluence)
Literature refer.Afterglow measures
GCN notices
Position info
Pisa, May 2009
AfterglowsAfterglows• Many bursts have good coverage of optical afterglows
• Combining with analysis of prompt lightcurves
Pisa, May 2009
Success of followupsSuccess of followups
The anti-solar HETE pointing was friendly for ground observers
and the frequency of GRB alerts was lower at the time of HETE
detections.
(until 2007)
Pisa, May 2009
HETE-2 Observations of HETE-2 Observations of GRB021211GRB021211
Crew et al. (2003) first HETE localization after 33 sec., OT reported by Fox & Price (GCN 1731) after 53’17”.
Pisa, May 2009
GRB021211: Afterglow Light Curve GRB021211: Afterglow Light Curve Relative to Those of Other GRBsRelative to Those of Other GRBs
The optical afterglow of some bursts is much fainter (~ 3 mag) than those previously observed: without HETE’s prompt localization, this GRB would very likely have been listed as “dark”, instead of “dim”. But it proves that at t < 10 min even “dim” afterglows may be bright (m ~ 13). This was very promising for Swift.
Pisa, May 2009
Amati relation revisitedAmati relation revisited
Amati relation extended to X-Ray Rich GRBs and to X-Ray Flashes
Pisa, May 2009
Amati relation extended to X-Ray Rich GRBs and to X-Ray Flashes
Pisa, May 2009
Lightcurve analysisLightcurve analysis
• trying to extract information besides T90/fluence
• developing methods for identification of peaks
need for sampling independent parameters
Lightcurve paradeLightcurve parade
Pisa, May 2009
Work in progressWork in progress
make catalogue ready for publicmake catalogue ready for public checking outliers linking the literature polishing the interface
prompt emission studiesprompt emission studies more detailed statistics comparison with other datasets (BATSE, Swift)
need for robust peak-analysis technique
better pseudo-redshift indicatorbetter pseudo-redshift indicator
Pisa, May 2009