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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"

11756 results found.

  1. GRB 041015 R band observations
  2. GRB041015: MASTER: Optical observations
  3. GRB041006: Fading X-ray Afterglow Observed with Chandra
  4. GRB 041015: Optical limit at Osaka University
  5. GRB 041015 - A long GRB detected by INTEGRAL
  6. GRB041006, optical observation in CrAO
  7. Search for SN light in XRF 040912 with MEGACAM
  8. GRB 041006 : optical follow-up observation at Lulin Observatory
  9. ROTSE-IIIa Observations of GRB 041006
  10. GRB 041006: Optical decay
  11. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  12. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  13. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  14. SGR 1806-20 still active
  15. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  16. GRB040924,optical observation
  17. GRB040924, RTT150 optical observation
  18. GRB040924 : Optical candidate observations at Lulin observatory
  19. GRB 040924: RTT150 optical observations
  20. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  21. XRF040916: continuing decay of OT
  22. GRB040912(=H3557): Candidate Optical Afterglow
  23. GRB040916 optical limits 17 min after GRB
  24. XRF 040912, identification of CXO sources
  25. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  26. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  27. GRB 040912: Optical Observations
  28. An intense burst from SGR1806-20
  29. GRB040912 : Kiso Optical follow-up observation
  30. HETE 3557: Optical observations
  31. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  32. GRB040903 - A XRF?
  33. GRB040827: analysis of the XMM-Newton observation
  34. Very bright burst detected from SGR 1806-20
  35. Possible GRB 040903 - further analysis
  36. GRB 040827 : peak flux
  37. Increase of SGR 1806-20 activity
  38. GRB 040812: Optical counterparts of CXO sources
  39. Bursting activity from SGR 1806-20 detected with IBAS
  40. Konus-Wind observation of GRB040810 (=H3489)
  41. GRB 040812: a long GRB detected by INTEGRAL
  42. GRB 040730: Optical observations
  43. GRB 040730: a long GRB detected with INTEGRAL
  44. Ongoing activity of SGR 1806-20
  45. XRF 040701 - optical observations of the decaying Chandra source
  46. XRF040701: Second-Epoch Chandra Observations
  47. Cancellation of IBAS/INTEGRAL GRB alerts
  48. XRF040701: VLA Observations
  49. XRF040701: First-Epoch Chandra Observations
  50. GRB040709 J,H-band observations
  51. GRB 040624: optical observations
  52. GRB 040624: R-band observations
  53. GRB 040624 - A long GRB detected with INTEGRAL
  54. IPN Summary of SGR1806-20 Activity in 2004
  55. SGR 1806-20: no IR variability of the proposed counterparts
  56. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  57. SGR 1806-20, potential NIR counterpart
  58. MASTER: HETE Alert 3274 optical observation
  59. Activivty of SGR 1806-20
  60. IPN triangulation of an intense intermediate burst from SGR1806-20
  61. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  62. GRB 040511: Second Epoch Optical Observations
  63. GRB 040511: Optical Observations
  64. GRB040511: Optical Observations
  65. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  66. IPN triangulation of GRB040425 (=H3183)
  67. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  68. GRB 040422: a long GRB detected with INTEGRAL
  69. GRB 040403, deep optical observations
  70. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  71. GRB 040403: Optical observations
  72. GRB 040403: a long GRB detected with INTEGRAL
  73. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  74. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  75. GRB040323: NIR Observations and Variable Object
  76. GRB 040323: a long GRB detected with INTEGRAL
  77. GRB040223: Deep NIR NTT data re-analysis
  78. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  79. MASTER: RXTE GRB040308 optical observation
  80. IBAS results on a burst from SGR1806-20
  81. INTEGRAL detection of activity from SGR1806-20
  82. IPN triangulation of GRB040228 (H3066, H3067)
  83. GRB 040223: further offline analysis
  84. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  85. GRB040106, likely optical afterglow
  86. GRB031220: observation at Univercity of Miyazaki
  87. GRB 040106 : peak flux
  88. IPN triangulation of an intermediate burst from SGR1806-20
  89. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  90. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  91. GRB031220: Palomar Observations
  92. GRB 031220: Subaru observation
  93. GRB 031220: Optical observation at Tokyo Tech
  94. GRB031220: ROTSE-IIIb Optical Limits
  95. GRB031220 : Optical Observation of Lulin Observatory
  96. GRB 2974 follow-up observations
  97. GRB 021203: A Normal GRB viewed far off axis?
  98. GRB 031203: Variable Radio Source
  99. GRB 031203: Optical/IR Astrometry
  100. GRB 031203: Deep NIR NTT & VLT observations

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