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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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"

42687 results found.

  1. XRF 040912: Radio Observations
  2. XRF 040916: Radio Observations
  3. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  4. XRF040916: continuing decay of OT
  5. TAROT Observations of GRB 040916 (HETE #3558)
  6. GRB040912(=H3557): Candidate Optical Afterglow
  7. XRF040916, optical observations
  8. XRF040916: Optical Transient Candidate by Subaru
  9. XRF 040912, identification of CXO sources
  10. XRF 040912 (=H3557): Spectral and Temporal Properties
  11. XRF040916, Ic observations
  12. XRF040916: optical follow-up observations
  13. XRF040912, BVRcIc field calibration
  14. XRF040916, BVRcIc field calibration
  15. GRB040916: Archival optical observations
  16. XRF 040916, optical follow-up
  17. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  18. GRB040916: Optical observations
  19. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  20. GRB040916 (= H3558): Improved Localization from HETE WXM
  21. GRB040916 (= H3558): A Long XRF Localized by HETE
  22. GRB040912 (= H3557): Chandra Observations Scheduled
  23. GRB 040912: Optical Observations
  24. GRB/XRF040912,optical observations
  25. GRB 040912, BVRI observations
  26. An intense burst from SGR1806-20
  27. GRB040912 : Kiso Optical follow-up observation
  28. IBAS GRB Alerts 1978-1980
  29. Optical observations of field of GRB040912
  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. GRB040903, REM near-IR observation
  35. GRB 040903 - INTEGRAL data analysis
  36. IBAS Alert 1974. Not a real GRB
  37. Very bright burst detected from SGR 1806-20
  38. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  39. Possible GRB 040903 detected with INTEGRAL
  40. GRB 040827 - Radio Observations
  41. GRB040825A: Optical observations
  42. GRB 040827: optical and NIR observations at the VLT
  43. GRB 040827: UKIRT - 2nd epoch K-band imaging
  44. GRB 040827: 2nd epoch of Magellan K-band imaging
  45. GRB 040827: K imaging - no evidence of variability
  46. GRB 040827: Detection of NIR afterglow
  47. GRB 040827: Possible detection of optical afterglow
  48. GRB 040827: RTT150 optical observations
  49. GRB040827 XMM-Newton observation
  50. MASTER: GRB040827 possible OT
  51. GRB 040825B: Optical observations
  52. GRB040827 optical observations
  53. GRB 040827 - A long GRB detected by INTEGRAL
  54. GRB040825B, BVRcIc field photometry
  55. GRB040825A, BVRcIc field photometry
  56. Increase of SGR 1806-20 activity
  57. GRB040825A: optical observations
  58. GRB040825B: optical observations
  59. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  60. GRB 040825A: Optical observations.
  61. GRB 040825: Optical observations
  62. XRF040812: possible afterglow second Chandra observation
  63. GRB 040812: Second epoch CXO Observations
  64. GRB040823,optical observation
  65. XRF040812: GMRT observations
  66. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  67. XRF 040812: optical observation at VLT
  68. GRB 040812: Optical counterparts of CXO sources
  69. XRF040812: possible afterglow
  70. CXO observation of GRB 040812
  71. Bursting activity from SGR 1806-20 detected with IBAS
  72. IPN/HETE localizations of GRB040810 (=H3489)
  73. GRB 040812: Keck and LCO optical observations
  74. GRB 040812: Keck and LCO observations
  75. GRB 040812: radio observations
  76. GRB040812, optical/IR observations
  77. Konus-Wind observation of GRB040810 (=H3489)
  78. GRB 040812: a long GRB detected by INTEGRAL
  79. GRB 040810: Optical observations of a limited region
  80. XRF040701: Optical Observations at ESO
  81. IPN/HETE triangulation of GRB040802 (=H3485)
  82. GRB 040730, infrared observations
  83. GRB 040730: Optical observations
  84. GRB 040730: a long GRB detected with INTEGRAL
  85. Ongoing activity of SGR 1806-20
  86. GRB040624: optical monitoring at TNG
  87. XRF 040701 - optical observations of the decaying Chandra source
  88. XRF040701: Second-Epoch Chandra Observations
  89. XRF040701: VLA Observations
  90. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  91. XRF040701: First-Epoch Chandra Observations
  92. IBAS Alert 1836: NOT a real GRB
  93. GRB040709 J,H-band observations
  94. GRB040624, optical observations
  95. XRF 040701, optical observations
  96. XRF040701 (=U11548): a bright XRF detected by HETE
  97. GRB 040624: optical observations
  98. Optical Observations of GRB040624
  99. GRB 040624: optical observations at TNG and VLT
  100. GRB 040624: R-band observations

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