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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

41625 results found.

  1. XRF 040812: optical observation at VLT
  2. GRB 040812: Optical counterparts of CXO sources
  3. XRF040812: possible afterglow
  4. CXO observation of GRB 040812
  5. Bursting activity from SGR 1806-20 detected with IBAS
  6. IPN/HETE localizations of GRB040810 (=H3489)
  7. GRB 040812: Keck and LCO optical observations
  8. GRB 040812: Keck and LCO observations
  9. GRB 040812: radio observations
  10. GRB040812, optical/IR observations
  11. GRB 040812: a long GRB detected by INTEGRAL
  12. GRB 040810: Optical observations of a limited region
  13. XRF040701: Optical Observations at ESO
  14. GRB 040730, infrared observations
  15. GRB 040730: Optical observations
  16. GRB 040730: a long GRB detected with INTEGRAL
  17. GRB040624: optical monitoring at TNG
  18. XRF 040701 - optical observations of the decaying Chandra source
  19. XRF040701: Second-Epoch Chandra Observations
  20. Cancellation of IBAS/INTEGRAL GRB alerts
  21. XRF040701: VLA Observations
  22. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  23. XRF040701: First-Epoch Chandra Observations
  24. GRB040709 J,H-band observations
  25. GRB040624, optical observations
  26. GRB040706:observation at University of Miyazaki
  27. XRF 040701, optical observations
  28. XRF040701 (=U11548): a bright XRF detected by HETE
  29. GRB 040624: optical observations
  30. Optical Observations of GRB040624
  31. GRB 040624: optical observations at TNG and VLT
  32. MASTER: GRB 040624 optical observation after 0,48d
  33. GRB 040624: R-band observations
  34. GRB 040624, optical observations
  35. GRB 040624 - A long GRB detected with INTEGRAL
  36. GRB 030329: Rebrightening of hyperluminal ejecta.
  37. IPN Summary of SGR1806-20 Activity in 2004
  38. GRB040511: Retraction of redshift identification
  39. SGR 1806-20: no IR variability of the proposed counterparts
  40. SGR 1806-20, potential NIR counterpart
  41. GRB 040606: Optical observations
  42. Activivty of SGR 1806-20
  43. GRB 040511, very fast decay?
  44. GRB 030324: Detection and Color of Host Galaxy
  45. GRB 040511: NIR observations with REM
  46. GRB040511: Redshift identifcation
  47. GRB 040511: Optical limit
  48. GRB040511: Candidate optical/NIR afterglow
  49. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  50. GRB 040511: Second Epoch Optical Observations
  51. GRB 040511: Optical observations
  52. GRB 040511: Optical Observations
  53. GRB040511: Optical Observations
  54. GRB040511: Optical Observations
  55. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  56. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  57. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  58. On Line Availability of Archival HETE Fregate Data and Lightcurves
  59. GRB040422: optical observations at Xinglong Observatory
  60. GRB040422: optical observations at CrAO
  61. GRB 040423 (=H3175): A Long GRB Localized by HETE
  62. GRB040422, optical observations at Loiano
  63. GRB040422 : I-band follow-up observation at Lulin Observatory
  64. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  65. GRB040422, BVRcIc field calibration
  66. GRB 040422,optical observation
  67. GRB040422: optical and NIR observations at the VLT
  68. GRB 040422: a long GRB detected with INTEGRAL
  69. GRB 040403, deep optical observations
  70. INTEGRAL-SPI/ACS GRB data: timing correction
  71. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  72. GRB 040403: Optical Observations
  73. GRB 040403 Optical Observations
  74. GRB 040403: Optical observations
  75. GRB 040403: optical observations
  76. GRB 040403: Optical Observations
  77. GRB 040403: a long GRB detected with INTEGRAL
  78. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  79. GRB040323: NIR Observations and Variable Object
  80. GRB 040323, a dark GRB ?
  81. GRB 040323: a long GRB detected with INTEGRAL
  82. GRB040223: Deep NIR NTT data re-analysis
  83. GRB 040223: XMM-Newton results
  84. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  85. GRB 031203, possible supernova
  86. MASTER: RXTE GRB040308 optical observation
  87. IBAS results on a burst from SGR1806-20
  88. INTEGRAL detection of activity from SGR1806-20
  89. RXTE GRB040229 optical observation: no candidate
  90. GRB 040228 Optical observations
  91. IPN triangulation of GRB040228 (H3066, H3067)
  92. GRB040228 : KISO optical follow-up observation
  93. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  94. GRB 040223: Deep NIR NTT observations
  95. GRB 040223 : Optical observation (non-detection)
  96. XMM-Newton Images of GRB 040223
  97. GRB 040223, VLA observations
  98. GRB 040223: REM IJK Observations
  99. GRB 040223 XMM-Newton observation ...
  100. GRB 031203 XMM-Newton observation

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