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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').
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"

36794 results found.

  1. GRB 040924, optical follow-up
  2. IPN triangulation of GRB040924 (H3564)
  3. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  4. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  5. XRF040916: continuing decay of OT
  6. TAROT Observations of GRB 040916 (HETE #3558)
  7. XRF040916, optical observations
  8. XRF040916: Optical Transient Candidate by Subaru
  9. GRB040916 optical limits 17 min after GRB
  10. XRF 040912 (=H3557): Spectral and Temporal Properties
  11. XRF040916, Ic observations
  12. XRF040912, BVRcIc field calibration
  13. XRF040916, BVRcIc field calibration
  14. GRB040916: Archival optical observations
  15. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  16. GRB040916: Optical observations
  17. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  18. GRB040912 (= H3557): Chandra Observations Scheduled
  19. GRB 040912: Optical Observations
  20. GRB/XRF040912,optical observations
  21. GRB 040912, BVRI observations
  22. Optical observations of GRB/XRF 040912 = HETE 3557
  23. An intense burst from SGR1806-20
  24. IBAS GRB Alerts 1978-1980
  25. Optical observations of field of GRB040912
  26. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  27. GRB 040827: XMM-Newton data
  28. GRB040903 - A XRF?
  29. GRB040827: analysis of the XMM-Newton observation
  30. GRB 040903 - INTEGRAL data analysis
  31. IBAS Alert 1974. Not a real GRB
  32. Very bright burst detected from SGR 1806-20
  33. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  34. Possible GRB 040903 - further analysis
  35. Possible GRB 040903 detected with INTEGRAL
  36. GRB 040827 - Radio Observations
  37. XMM-Newton Images of GRB 040827
  38. GRB 040827: optical and NIR observations at the VLT
  39. GRB 040827: UKIRT - 2nd epoch K-band imaging
  40. GRB 040827: 2nd epoch of Magellan K-band imaging
  41. GRB 040827: K imaging - no evidence of variability
  42. GRB 040827: Detection of NIR afterglow
  43. GRB 040827: Possible detection of optical afterglow
  44. GRB 040827: RTT150 optical observations
  45. GRB040825A: optical limit before GRB
  46. GRB 040825B: Optical observations
  47. GRB040827 optical observations
  48. GRB 040827 : Planned XMM-Newton observation
  49. GRB 040827 - Refined position
  50. GRB 040827 : peak flux
  51. GRB 040827 - A long GRB detected by INTEGRAL
  52. GRB040825B, BVRcIc field photometry
  53. GRB040825A, BVRcIc field photometry
  54. GCN GRB OBSERBATION REPORT
  55. GRB 040825A,optical observations
  56. Increase of SGR 1806-20 activity
  57. GRB 040825A: Optical observations.
  58. GRB040825B: Correction to GCN 2657
  59. GRB 040825: Optical observations
  60. GRB 040812: Second epoch CXO Observations
  61. GRB040823,optical observation
  62. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  63. XRF 040812: optical observation at VLT
  64. GRB 040812: Optical counterparts of CXO sources
  65. XRF040812: possible afterglow
  66. CXO observation of GRB 040812
  67. IPN/HETE localizations of GRB040810 (=H3489)
  68. GRB 040812: Keck and LCO optical observations
  69. GRB 040812: Keck and LCO observations
  70. GRB 040812: radio observations
  71. GRB040812, optical/IR observations
  72. Konus-Wind observation of GRB040810 (=H3489)
  73. GRB 040812: a long GRB detected by INTEGRAL
  74. GRB 040810: Optical observations of a limited region
  75. IPN/HETE triangulation of GRB040802 (=H3485)
  76. GRB 040730, infrared observations
  77. GRB 040730: Optical observations
  78. GRB 040730: a long GRB detected with INTEGRAL
  79. Ongoing activity of SGR 1806-20
  80. GRB040624: optical monitoring at TNG
  81. Cancellation of IBAS/INTEGRAL GRB alerts
  82. IBAS Alert 1836: NOT a real GRB
  83. GRB040709 J,H-band observations
  84. GRB 040624: optical observations
  85. GRB 040624: optical observations at TNG and VLT
  86. MASTER: GRB 040624 optical observation after 0,48d
  87. GRB 040624: R-band observations
  88. GRB 040624, optical observations
  89. GRB 040624 - A long GRB detected with INTEGRAL
  90. GRB 030329: Rebrightening of hyperluminal ejecta.
  91. IPN Summary of SGR1806-20 Activity in 2004
  92. GRB040511: Retraction of redshift identification
  93. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  94. GRB 040606: Optical observations
  95. MASTER: HETE Alert 3274 optical observation
  96. Activivty of SGR 1806-20
  97. IPN triangulation of an intense intermediate burst from SGR1806-20
  98. GRB 040511, very fast decay?
  99. GRB 030324: Detection and Color of Host Galaxy
  100. GRB 040511: NIR observations with REM

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