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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