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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32713 results found.

  1. XRF040916, BVRcIc field calibration
  2. GRB040916: Archival optical observations
  3. XRF 040916, optical follow-up
  4. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  5. GRB040916: Optical observations
  6. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  7. GRB040916 (= H3558): A Long XRF Localized by HETE
  8. GRB040912 (= H3557): Chandra Observations Scheduled
  9. GRB 040912, BVRI observations
  10. GRB040912 : Kiso Optical follow-up observation
  11. IBAS GRB Alerts 1978-1980
  12. Optical observations of field of GRB040912
  13. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  14. GRB040903 - A XRF?
  15. GRB040827: analysis of the XMM-Newton observation
  16. GRB040903, REM near-IR observation
  17. GRB 040903 - INTEGRAL data analysis
  18. Very bright burst detected from SGR 1806-20
  19. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  20. Possible GRB 040903 - further analysis
  21. GRB 040827 - Radio Observations
  22. XMM-Newton Images of GRB 040827
  23. GRB040825A: Optical observations
  24. GRB040825A: Optical observations
  25. GRB 040827: optical and NIR observations at the VLT
  26. GRB 040827: UKIRT - 2nd epoch K-band imaging
  27. GRB 040827: 2nd epoch of Magellan K-band imaging
  28. GRB 040827: K imaging - no evidence of variability
  29. GRB 040827: Detection of NIR afterglow
  30. GRB 040827: Possible detection of optical afterglow
  31. GRB 040827: RTT150 optical observations
  32. MASTER: GRB040827 possible OT
  33. GRB 040825B: Optical observations
  34. GRB040827 optical observations
  35. GRB 040827 - Refined position
  36. GRB040825B, BVRcIc field photometry
  37. GCN GRB OBSERBATION REPORT
  38. GRB040825B: optical observations
  39. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  40. GRB040825B: Correction to GCN 2657
  41. XRF040812: possible afterglow second Chandra observation
  42. GRB 040812: Second epoch CXO Observations
  43. XRF040812: GMRT observations
  44. XRF 040812: optical observation at VLT
  45. GRB 040812: Optical counterparts of CXO sources
  46. XRF040812: possible afterglow
  47. CXO observation of GRB 040812
  48. IPN/HETE localizations of GRB040810 (=H3489)
  49. GRB 040812: Keck and LCO optical observations
  50. GRB 040812: Keck and LCO observations
  51. GRB 040812: radio observations
  52. GRB040812, optical/IR observations
  53. XRF040701: Optical Observations at ESO
  54. IPN/HETE triangulation of GRB040802 (=H3485)
  55. GRB 040730, infrared observations
  56. GRB 040730: Optical observations
  57. Ongoing activity of SGR 1806-20
  58. GRB040624: optical monitoring at TNG
  59. XRF 040701 - optical observations of the decaying Chandra source
  60. XRF040701: Second-Epoch Chandra Observations
  61. XRF040701: VLA Observations
  62. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  63. XRF040701: First-Epoch Chandra Observations
  64. GRB040709 J,H-band observations
  65. GRB040624, optical observations
  66. XRF 040701, optical observations
  67. GRB 040624: optical observations
  68. Optical Observations of GRB040624
  69. GRB 040624: optical observations at TNG and VLT
  70. GRB 040624: R-band observations
  71. GRB 040624, optical observations
  72. GRB 030329: Rebrightening of hyperluminal ejecta.
  73. IPN Summary of SGR1806-20 Activity in 2004
  74. GRB040511: Retraction of redshift identification
  75. SGR 1806-20: no IR variability of the proposed counterparts
  76. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  77. Activivty of SGR 1806-20
  78. GRB 040511, very fast decay?
  79. GRB 030324: Detection and Color of Host Galaxy
  80. GRB 040511: NIR observations with REM
  81. GRB040511: Redshift identifcation
  82. GRB 040511: Optical limit
  83. GRB040511: Candidate optical/NIR afterglow
  84. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  85. GRB 040511: Second Epoch Optical Observations
  86. GRB 040511: Optical observations
  87. GRB 040511: Optical Observations
  88. GRB040511: Optical Observations
  89. GRB040511: Optical Observations
  90. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  91. IPN triangulation of GRB040425 (=H3183)
  92. On Line Availability of Archival HETE Fregate Data and Lightcurves
  93. GRB040422, optical observations at Loiano
  94. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  95. GRB040422, BVRcIc field calibration
  96. GRB040422: optical and NIR observations at the VLT
  97. GRB 040403, deep optical observations
  98. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  99. GRB 040403: Optical Observations
  100. GRB 040403 Optical Observations

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