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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"

37803 results found.

  1. GRB040924: KAIT observations
  2. GRB040924: Afterglow magnitude at t=17.5hr
  3. GRB 040924: WSRT Radio Observations
  4. GRB 040924: NIR finding chart
  5. GRB040924 : Optical candidate observations at Lulin observatory
  6. GRB040924 : Optical candidate observations at Lulin observatory
  7. GRB 040924: Subaru NIR observation
  8. GRB 040924: RTT150 optical observations
  9. GRB 040924, optical follow-up
  10. IPN triangulation of GRB040924 (H3564)
  11. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  12. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  13. XRF040916: continuing decay of OT
  14. TAROT Observations of GRB 040916 (HETE #3558)
  15. XRF040916, optical observations
  16. XRF040916: Optical Transient Candidate by Subaru
  17. GRB040916 optical limits 17 min after GRB
  18. XRF 040912 (=H3557): Spectral and Temporal Properties
  19. XRF040916, Ic observations
  20. XRF040912, BVRcIc field calibration
  21. XRF040916, BVRcIc field calibration
  22. GRB040916: Archival optical observations
  23. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  24. GRB040916: Optical observations
  25. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  26. GRB040912 (= H3557): Chandra Observations Scheduled
  27. GRB 040912: Optical Observations
  28. GRB/XRF040912,optical observations
  29. GRB 040912, BVRI observations
  30. Optical observations of GRB/XRF 040912 = HETE 3557
  31. An intense burst from SGR1806-20
  32. IBAS GRB Alerts 1978-1980
  33. Optical observations of field of GRB040912
  34. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  35. GRB 040827: XMM-Newton data
  36. GRB040903 - A XRF?
  37. GRB040827: analysis of the XMM-Newton observation
  38. GRB 040903 - INTEGRAL data analysis
  39. IBAS Alert 1974. Not a real GRB
  40. Very bright burst detected from SGR 1806-20
  41. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  42. Possible GRB 040903 - further analysis
  43. Possible GRB 040903 detected with INTEGRAL
  44. GRB 040827 - Radio Observations
  45. XMM-Newton Images of GRB 040827
  46. GRB 040827: optical and NIR observations at the VLT
  47. GRB 040827: UKIRT - 2nd epoch K-band imaging
  48. GRB 040827: 2nd epoch of Magellan K-band imaging
  49. GRB 040827: K imaging - no evidence of variability
  50. GRB 040827: Detection of NIR afterglow
  51. GRB 040827: Possible detection of optical afterglow
  52. GRB 040827: RTT150 optical observations
  53. GRB040825A: optical limit before GRB
  54. GRB 040825B: Optical observations
  55. GRB040827 optical observations
  56. GRB 040827 : Planned XMM-Newton observation
  57. GRB 040827 - Refined position
  58. GRB 040827 : peak flux
  59. GRB 040827 - A long GRB detected by INTEGRAL
  60. GRB040825B, BVRcIc field photometry
  61. GRB040825A, BVRcIc field photometry
  62. GCN GRB OBSERBATION REPORT
  63. GRB 040825A,optical observations
  64. Increase of SGR 1806-20 activity
  65. GRB 040825A: Optical observations.
  66. GRB040825B: Correction to GCN 2657
  67. GRB 040825: Optical observations
  68. GRB 040812: Second epoch CXO Observations
  69. GRB040823,optical observation
  70. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  71. XRF 040812: optical observation at VLT
  72. GRB 040812: Optical counterparts of CXO sources
  73. XRF040812: possible afterglow
  74. CXO observation of GRB 040812
  75. IPN/HETE localizations of GRB040810 (=H3489)
  76. GRB 040812: Keck and LCO optical observations
  77. GRB 040812: Keck and LCO observations
  78. GRB 040812: radio observations
  79. GRB040812, optical/IR observations
  80. Konus-Wind observation of GRB040810 (=H3489)
  81. GRB 040812: a long GRB detected by INTEGRAL
  82. GRB 040810: Optical observations of a limited region
  83. IPN/HETE triangulation of GRB040802 (=H3485)
  84. GRB 040730, infrared observations
  85. GRB 040730: Optical observations
  86. GRB 040730: a long GRB detected with INTEGRAL
  87. Ongoing activity of SGR 1806-20
  88. GRB040624: optical monitoring at TNG
  89. Cancellation of IBAS/INTEGRAL GRB alerts
  90. IBAS Alert 1836: NOT a real GRB
  91. GRB040709 J,H-band observations
  92. GRB 040624: optical observations
  93. GRB 040624: optical observations at TNG and VLT
  94. MASTER: GRB 040624 optical observation after 0,48d
  95. GRB 040624: R-band observations
  96. GRB 040624, optical observations
  97. GRB 040624 - A long GRB detected with INTEGRAL
  98. GRB 030329: Rebrightening of hyperluminal ejecta.
  99. IPN Summary of SGR1806-20 Activity in 2004
  100. GRB040511: Retraction of redshift identification

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