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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"

20362 results found.

  1. GRB040827 XMM-Newton observation
  2. GRB040825A: optical limit before GRB
  3. GRB 040825B: Optical observations
  4. GRB 040827 : Planned XMM-Newton observation
  5. GRB040825B, BVRcIc field photometry
  6. GRB040825A, BVRcIc field photometry
  7. GCN GRB OBSERBATION REPORT
  8. GRB 040825A,optical observations
  9. GRB040825A: optical observations
  10. GRB040825B: optical observations
  11. MASTER: GRB040825b optical observation
  12. GRB 040812: Second epoch CXO Observations
  13. GRB040823,optical observation
  14. XRF040812: GMRT observations
  15. XRF 040812: optical observation at VLT
  16. GRB 040812: Optical counterparts of CXO sources
  17. CXO observation of GRB 040812
  18. IPN/HETE localizations of GRB040810 (=H3489)
  19. GRB040812, optical/IR observations
  20. Konus-Wind observation of GRB040810 (=H3489)
  21. GRB 040810: Optical observations of a limited region
  22. XRF040701: Optical Observations at ESO
  23. GRB 040730, infrared observations
  24. GRB040624: optical monitoring at TNG
  25. XRF 040701 - optical observations of the decaying Chandra source
  26. XRF040701: Second-Epoch Chandra Observations
  27. XRF040701: VLA Observations
  28. XRF040701: First-Epoch Chandra Observations
  29. GRB040624, optical observations
  30. GRB040706:observation at University of Miyazaki
  31. Optical Observations of GRB040624
  32. GRB 040624: optical observations at TNG and VLT
  33. MASTER: GRB 040624 optical observation after 0,48d
  34. GRB 040624, optical observations
  35. GRB 030329: Rebrightening of hyperluminal ejecta.
  36. IPN Summary of SGR1806-20 Activity in 2004
  37. SGR 1806-20: no IR variability of the proposed counterparts
  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. GRB 040511, very fast decay?
  43. GRB 030324: Detection and Color of Host Galaxy
  44. GRB 040511: NIR observations with REM
  45. GRB040511: Candidate optical/NIR afterglow
  46. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  47. GRB 040511: Second Epoch Optical Observations
  48. IBAS GRB Alerts 1781-4
  49. GRB 040511: Optical observations
  50. GRB 040511: Optical Observations
  51. GRB040511: Optical Observations
  52. GRB040511: Optical Observations
  53. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  54. GRB 040423 (=H3175): A Long GRB Localized by HETE
  55. GRB040422 : I-band follow-up observation at Lulin Observatory
  56. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  57. GRB040422, BVRcIc field calibration
  58. GRB 040422,optical observation
  59. GRB 040403, deep optical observations
  60. MASTER: HETE Alert 3163, 3167 technical optical observation
  61. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  62. GRB 040403: Optical observations
  63. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  64. GRB040323: NIR Observations and Variable Object
  65. GRB 040323, a dark GRB ?
  66. GRB040223, improved XMM position
  67. GRB 031203, possible supernova
  68. MASTER: RXTE GRB040308 optical observation
  69. IBAS results on a burst from SGR1806-20
  70. GRB040228 : KISO optical follow-up observation
  71. GRB 040223: Deep NIR NTT observations
  72. GRB 040223 : Optical observation (non-detection)
  73. XMM-Newton Images of GRB 040223
  74. GRB 040223, VLA observations
  75. GRB 040223: REM IJK Observations
  76. GRB 040223 XMM-Newton observation ...
  77. GRB 031203 XMM-Newton observation
  78. GRB031111, optical observations
  79. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  80. GRB040106, follow-up radio observations
  81. GRB040106: refined X-ray transient position
  82. GRB 031220: Optical observations of Chandra X-ray sources
  83. XMM-Newton Images of GRB 040106
  84. GRB031220: observation at Univercity of Miyazaki
  85. XMM-Newton observation of GRB040106
  86. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  87. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  88. GRB 031220 : Kyoto Optical Observation
  89. GRB 031220: Subaru observation
  90. GRB 031220: Optical observation at Tokyo Tech
  91. GRB 2974 follow-up observations
  92. GRB031203, improved XMM position
  93. GRB 021203: A Normal GRB viewed far off axis?
  94. XMM-Newton Observations of GRB031203: Preliminary Images
  95. GRB 031203: Optical/IR Astrometry
  96. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  97. XMM-Newton Observation of GRB031203
  98. GRB 031203: Deep NIR NTT & VLT observations
  99. XMM-Newton Observation of GRB031203
  100. GRB 031203: Further reports on December 4 observations

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