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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').
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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"

35942 results found.

  1. GRB040825A, BVRcIc field photometry
  2. GCN GRB OBSERBATION REPORT
  3. GRB 040825A,optical observations
  4. Increase of SGR 1806-20 activity
  5. GRB 040825A: Optical observations.
  6. GRB040825B: Correction to GCN 2657
  7. GRB 040825: Optical observations
  8. GRB 040812: Second epoch CXO Observations
  9. GRB040823,optical observation
  10. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  11. XRF 040812: optical observation at VLT
  12. GRB 040812: Optical counterparts of CXO sources
  13. XRF040812: possible afterglow
  14. CXO observation of GRB 040812
  15. IPN/HETE localizations of GRB040810 (=H3489)
  16. GRB 040812: Keck and LCO optical observations
  17. GRB 040812: Keck and LCO observations
  18. GRB 040812: radio observations
  19. GRB040812, optical/IR observations
  20. Konus-Wind observation of GRB040810 (=H3489)
  21. GRB 040812: a long GRB detected by INTEGRAL
  22. GRB 040810: Optical observations of a limited region
  23. IPN/HETE triangulation of GRB040802 (=H3485)
  24. GRB 040730, infrared observations
  25. GRB 040730: Optical observations
  26. GRB 040730: a long GRB detected with INTEGRAL
  27. Ongoing activity of SGR 1806-20
  28. GRB040624: optical monitoring at TNG
  29. Cancellation of IBAS/INTEGRAL GRB alerts
  30. IBAS Alert 1836: NOT a real GRB
  31. GRB040709 J,H-band observations
  32. GRB 040624: optical observations
  33. GRB 040624: optical observations at TNG and VLT
  34. MASTER: GRB 040624 optical observation after 0,48d
  35. GRB 040624: R-band observations
  36. GRB 040624, optical observations
  37. GRB 040624 - A long GRB detected with INTEGRAL
  38. GRB 030329: Rebrightening of hyperluminal ejecta.
  39. IPN Summary of SGR1806-20 Activity in 2004
  40. GRB040511: Retraction of redshift identification
  41. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  42. GRB 040606: Optical observations
  43. MASTER: HETE Alert 3274 optical observation
  44. Activivty of SGR 1806-20
  45. IPN triangulation of an intense intermediate burst from SGR1806-20
  46. GRB 040511, very fast decay?
  47. GRB 030324: Detection and Color of Host Galaxy
  48. GRB 040511: NIR observations with REM
  49. GRB040511: Redshift identifcation
  50. GRB 040511: Optical limit
  51. IBAS GRB Alerts n.1785 to 1791
  52. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  53. GRB 040511: Second Epoch Optical Observations
  54. IBAS GRB Alerts 1781-4
  55. GRB 040511: Optical observations
  56. GRB 040511: Optical Observations
  57. GRB040511: Optical Observations
  58. GRB040511: Optical Observations
  59. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  60. IBAS GRB Alert number 1774: NOT a real GRB
  61. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  62. IBAS Alerts 1771 and 1772: NOT a real GRB
  63. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  64. IPN triangulation of GRB040425 (=H3183)
  65. GRB040422: optical observations at CrAO
  66. GRB 040423 (=H3175): A Long GRB Localized by HETE
  67. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  68. GRB040422, BVRcIc field calibration
  69. GRB 040422,optical observation
  70. GRB 040422: a long GRB detected with INTEGRAL
  71. GRB 040403, deep optical observations
  72. INTEGRAL-SPI/ACS GRB data: timing correction
  73. IBAS GRB alerts 1739, 1740, 1741
  74. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  75. GRB 040403: Optical Observations
  76. GRB 040403 Optical Observations
  77. GRB 040403: Optical observations
  78. GRB 040403: optical observations
  79. GRB 040403: Optical Observations
  80. GRB 040403: a long GRB detected with INTEGRAL
  81. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  82. IBAS GRB Alert 1694
  83. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  84. GRB 040323, a dark GRB ?
  85. short hard GRB 040322
  86. GRB 040323: a long GRB detected with INTEGRAL
  87. IBAS GRB alerts 1679, 1680, 1681
  88. GRB040223: Deep NIR NTT data re-analysis
  89. GRB 040223: XMM-Newton results
  90. GRB040223, improved XMM position
  91. IBAS Alert 1678: not a GRB
  92. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  93. GRB 031203, possible supernova
  94. GRB 040228 Optical observations
  95. IPN triangulation of GRB040228 (H3066, H3067)
  96. GRB040228 : KISO optical follow-up observation
  97. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  98. GRB 040223: Deep NIR NTT observations
  99. GRB 040223 : Optical observation (non-detection)
  100. XMM-Newton Images of GRB 040223

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