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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"

36144 results found.

  1. Increase of SGR 1806-20 activity
  2. GRB 040825A: Optical observations.
  3. GRB040825B: Correction to GCN 2657
  4. GRB 040825: Optical observations
  5. GRB 040812: Second epoch CXO Observations
  6. GRB040823,optical observation
  7. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  8. XRF 040812: optical observation at VLT
  9. GRB 040812: Optical counterparts of CXO sources
  10. XRF040812: possible afterglow
  11. CXO observation of GRB 040812
  12. IPN/HETE localizations of GRB040810 (=H3489)
  13. GRB 040812: Keck and LCO optical observations
  14. GRB 040812: Keck and LCO observations
  15. GRB 040812: radio observations
  16. GRB040812, optical/IR observations
  17. Konus-Wind observation of GRB040810 (=H3489)
  18. GRB 040812: a long GRB detected by INTEGRAL
  19. GRB 040810: Optical observations of a limited region
  20. IPN/HETE triangulation of GRB040802 (=H3485)
  21. GRB 040730, infrared observations
  22. GRB 040730: Optical observations
  23. GRB 040730: a long GRB detected with INTEGRAL
  24. Ongoing activity of SGR 1806-20
  25. GRB040624: optical monitoring at TNG
  26. Cancellation of IBAS/INTEGRAL GRB alerts
  27. IBAS Alert 1836: NOT a real GRB
  28. GRB040709 J,H-band observations
  29. GRB 040624: optical observations
  30. GRB 040624: optical observations at TNG and VLT
  31. MASTER: GRB 040624 optical observation after 0,48d
  32. GRB 040624: R-band observations
  33. GRB 040624, optical observations
  34. GRB 040624 - A long GRB detected with INTEGRAL
  35. GRB 030329: Rebrightening of hyperluminal ejecta.
  36. IPN Summary of SGR1806-20 Activity in 2004
  37. GRB040511: Retraction of redshift identification
  38. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  39. GRB 040606: Optical observations
  40. MASTER: HETE Alert 3274 optical observation
  41. Activivty of SGR 1806-20
  42. IPN triangulation of an intense intermediate burst from SGR1806-20
  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. IBAS GRB Alerts n.1785 to 1791
  49. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  50. GRB 040511: Second Epoch Optical Observations
  51. IBAS GRB Alerts 1781-4
  52. GRB 040511: Optical observations
  53. GRB 040511: Optical Observations
  54. GRB040511: Optical Observations
  55. GRB040511: Optical Observations
  56. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  57. IBAS GRB Alert number 1774: NOT a real GRB
  58. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  59. IBAS Alerts 1771 and 1772: NOT a real GRB
  60. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  61. IPN triangulation of GRB040425 (=H3183)
  62. On Line Availability of Archival HETE Fregate Data and Lightcurves
  63. GRB040422: optical observations at CrAO
  64. GRB 040423 (=H3175): A Long GRB Localized by HETE
  65. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  66. GRB040422, BVRcIc field calibration
  67. GRB 040422,optical observation
  68. GRB 040422: a long GRB detected with INTEGRAL
  69. GRB 040403, deep optical observations
  70. INTEGRAL-SPI/ACS GRB data: timing correction
  71. IBAS GRB alerts 1739, 1740, 1741
  72. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  73. GRB 040403: Optical Observations
  74. GRB 040403 Optical Observations
  75. GRB 040403: Optical observations
  76. GRB 040403: optical observations
  77. GRB 040403: Optical Observations
  78. GRB 040403: a long GRB detected with INTEGRAL
  79. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  80. IBAS GRB Alert 1694
  81. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  82. GRB 040323, a dark GRB ?
  83. short hard GRB 040322
  84. GRB 040323: a long GRB detected with INTEGRAL
  85. IBAS GRB alerts 1679, 1680, 1681
  86. GRB040223: Deep NIR NTT data re-analysis
  87. GRB 040223: XMM-Newton results
  88. GRB040223, improved XMM position
  89. IBAS Alert 1678: not a GRB
  90. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  91. GRB 031203, possible supernova
  92. GRB 040228 Optical observations
  93. IPN triangulation of GRB040228 (H3066, H3067)
  94. GRB040228 : KISO optical follow-up observation
  95. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  96. GRB 040223: Deep NIR NTT observations
  97. GRB 040223 : Optical observation (non-detection)
  98. XMM-Newton Images of GRB 040223
  99. GRB 040223, VLA observations
  100. GRB 040223: REM IJK Observations

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