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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"

25036 results found.

  1. TAROT Observations of GRB 040916 (HETE #3558)
  2. GRB040912(=H3557): Candidate Optical Afterglow
  3. XRF040916, optical observations
  4. XRF 040912, identification of CXO sources
  5. XRF040912, BVRcIc field calibration
  6. XRF040916, BVRcIc field calibration
  7. GRB040916: Archival optical observations
  8. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  9. GRB040916: Optical observations
  10. GRB040912 (= H3557): Chandra Observations Scheduled
  11. GRB 040912: Optical Observations
  12. GRB/XRF040912,optical observations
  13. GRB 040912, BVRI observations
  14. Optical observations of field of GRB040912
  15. HETE 3557: Optical observations
  16. GRB040903 - A XRF?
  17. GRB040827: analysis of the XMM-Newton observation
  18. GRB040903, REM near-IR observation
  19. Very bright burst detected from SGR 1806-20
  20. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  21. Possible GRB 040903 - further analysis
  22. GRB 040827 - Radio Observations
  23. XMM-Newton Images of GRB 040827
  24. GRB 040827: optical and NIR observations at the VLT
  25. GRB 040827: UKIRT - 2nd epoch K-band imaging
  26. GRB 040827: 2nd epoch of Magellan K-band imaging
  27. GRB 040827: K imaging - no evidence of variability
  28. GRB 040827: Detection of NIR afterglow
  29. GRB040827 XMM-Newton observation
  30. GRB040825A: optical limit before GRB
  31. GRB 040825B: Optical observations
  32. GRB 040827 : Planned XMM-Newton observation
  33. GRB040825B, BVRcIc field photometry
  34. GRB040825A, BVRcIc field photometry
  35. GCN GRB OBSERBATION REPORT
  36. GRB 040825A,optical observations
  37. GRB040825A: optical observations
  38. GRB040825B: optical observations
  39. MASTER: GRB040825b optical observation
  40. GRB 040825: Optical observations
  41. XRF040812: possible afterglow second Chandra observation
  42. GRB 040812: Second epoch CXO Observations
  43. GRB040823,optical observation
  44. XRF040812: GMRT observations
  45. XRF 040812: optical observation at VLT
  46. GRB 040812: Optical counterparts of CXO sources
  47. XRF040812: possible afterglow
  48. CXO observation of GRB 040812
  49. GRB 040812: radio observations
  50. GRB040812, optical/IR observations
  51. GRB 040812: a long GRB detected by INTEGRAL
  52. XRF040701: Optical Observations at ESO
  53. GRB 040730, infrared observations
  54. GRB 040730: a long GRB detected with INTEGRAL
  55. Ongoing activity of SGR 1806-20
  56. GRB040624: optical monitoring at TNG
  57. XRF 040701 - optical observations of the decaying Chandra source
  58. XRF040701: Second-Epoch Chandra Observations
  59. XRF040701: VLA Observations
  60. XRF040701: First-Epoch Chandra Observations
  61. GRB040624, optical observations
  62. GRB040706:observation at University of Miyazaki
  63. Optical Observations of GRB040624
  64. GRB 040624: optical observations at TNG and VLT
  65. MASTER: GRB 040624 optical observation after 0,48d
  66. GRB 040624, optical observations
  67. GRB 040624 - A long GRB detected with INTEGRAL
  68. GRB 030329: Rebrightening of hyperluminal ejecta.
  69. IPN Summary of SGR1806-20 Activity in 2004
  70. SGR 1806-20: no IR variability of the proposed counterparts
  71. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  72. SGR 1806-20, potential NIR counterpart
  73. GRB 040606: Optical observations
  74. MASTER: HETE Alert 3274 optical observation
  75. Activivty of SGR 1806-20
  76. GRB 040511, very fast decay?
  77. GRB 030324: Detection and Color of Host Galaxy
  78. GRB 040511: NIR observations with REM
  79. GRB040511: Candidate optical/NIR afterglow
  80. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  81. GRB 040511: Second Epoch Optical Observations
  82. GRB 040511: Optical observations
  83. GRB 040511: Optical Observations
  84. GRB040511: Optical Observations
  85. GRB040511: Optical Observations
  86. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  87. GRB 040423 (=H3175): A Long GRB Localized by HETE
  88. GRB040422 : I-band follow-up observation at Lulin Observatory
  89. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  90. GRB040422, BVRcIc field calibration
  91. GRB 040422,optical observation
  92. GRB 040422: a long GRB detected with INTEGRAL
  93. GRB 040403, deep optical observations
  94. MASTER: HETE Alert 3163, 3167 technical optical observation
  95. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  96. GRB 040403: Optical observations
  97. GRB 040403: a long GRB detected with INTEGRAL
  98. GRB040323: NIR Observations and Variable Object
  99. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  100. GRB 040323, a dark GRB ?

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