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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"

45463 results found.

  1. GRB 030324: Detection and Color of Host Galaxy
  2. GRB 040511: NIR observations with REM
  3. GRB040511: Redshift identifcation
  4. GRB 040511: Optical limit
  5. GRB040511: Candidate optical/NIR afterglow
  6. IBAS GRB Alerts n.1785 to 1791
  7. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  8. GRB 040511: Second Epoch Optical Observations
  9. GRB 040511: Optical observations
  10. GRB 040511: Optical Observations
  11. GRB040511: Optical Observations
  12. GRB040511: Optical Observations
  13. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  14. IBAS GRB Alert number 1774: NOT a real GRB
  15. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  16. IBAS Alerts 1771 and 1772: NOT a real GRB
  17. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  18. IPN triangulation of GRB040425 (=H3183)
  19. On Line Availability of Archival HETE Fregate Data and Lightcurves
  20. GRB040422: optical observations at Xinglong Observatory
  21. GRB040422: optical observations at CrAO
  22. GRB 040423 (=H3175): A Long GRB Localized by HETE
  23. GRB040422, optical observations at Loiano
  24. GRB040422 : I-band follow-up observation at Lulin Observatory
  25. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  26. GRB040422, BVRcIc field calibration
  27. GRB 040422,optical observation
  28. GRB040422: optical and NIR observations at the VLT
  29. GRB 040422: a long GRB detected with INTEGRAL
  30. GRB 040403, deep optical observations
  31. MASTER: HETE Alert 3163, 3167 technical optical observation
  32. INTEGRAL-SPI/ACS GRB data: timing correction
  33. IBAS GRB alerts 1739, 1740, 1741
  34. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  35. GRB 040403: Optical Observations
  36. GRB 040403 Optical Observations
  37. GRB 040403: Optical observations
  38. GRB 040403: optical observations
  39. GRB 040403: Optical Observations
  40. GRB 040403: a long GRB detected with INTEGRAL
  41. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  42. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  43. IBAS GRB Alert 1694
  44. GRB040323: NIR Observations and Variable Object
  45. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  46. GRB 040323, a dark GRB ?
  47. short hard GRB 040322
  48. GRB 040323: a long GRB detected with INTEGRAL
  49. IBAS GRB alerts 1679, 1680, 1681
  50. GRB040223: Deep NIR NTT data re-analysis
  51. GRB 040223: XMM-Newton results
  52. GRB040223, improved XMM position
  53. IBAS Alert 1678: not a GRB
  54. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  55. GRB 031203, possible supernova
  56. MASTER: RXTE GRB040308 optical observation
  57. IBAS results on a burst from SGR1806-20
  58. INTEGRAL detection of activity from SGR1806-20
  59. RXTE GRB040229 optical observation: no candidate
  60. GRB 040228 Optical observations
  61. IPN triangulation of GRB040228 (H3066, H3067)
  62. GRB040228 : KISO optical follow-up observation
  63. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  64. GRB 040223: Deep NIR NTT observations
  65. GRB 040223 : Optical observation (non-detection)
  66. XMM-Newton Images of GRB 040223
  67. GRB 040223, VLA observations
  68. GRB 040223: REM IJK Observations
  69. GRB 040223 XMM-Newton observation ...
  70. GRB 031203 XMM-Newton observation
  71. GRB 040223 : Planned XMM-Newton observation
  72. GRB 040106 : Planned XMM-Newton observation
  73. GRB 040223: further offline analysis
  74. GRB 040223: a long GRB detected with INTEGRAL
  75. GRB031111, optical observations
  76. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  77. GRB031203: Chandra Observations
  78. GRB040106, follow-up radio observations
  79. GRB040106: refined X-ray transient position
  80. Follow-up on IBAS GRB Alert 1379
  81. IBAS GRB alert 1379
  82. SN 2003dh/GRB030329 late-time optical spectroscopy
  83. GRB040106, Radio Observations
  84. GRB040106, likely optical afterglow
  85. GRB040106: Second Epoch Optical Observations
  86. GRB 031220: Optical observations of Chandra X-ray sources
  87. XMM-Newton Images of GRB 040106
  88. GRB040106: optical observations with REM+ROSS
  89. GRB031220: observation at Univercity of Miyazaki
  90. GRB 040106: Optical observations
  91. XMM-Newton observation of GRB040106
  92. GRB 040106 : Planned XMM-Newton observation
  93. GRB 040106 : peak flux
  94. GRB 040106 : a long GRB detected with INTEGRAL
  95. IPN triangulation of an intermediate burst from SGR1806-20
  96. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  97. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  98. GRB031225a triangulation (annulus)
  99. IPN triangulation of GRB031219 (large error box)
  100. GRB031220: Palomar Observations

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