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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"

35952 results found.

  1. GRB 040827: Possible detection of optical afterglow
  2. GRB 040827: RTT150 optical observations
  3. GRB040825A: optical limit before GRB
  4. GRB 040825B: Optical observations
  5. GRB040827 optical observations
  6. GRB 040827 : Planned XMM-Newton observation
  7. GRB 040827 - Refined position
  8. GRB 040827 : peak flux
  9. GRB 040827 - A long GRB detected by INTEGRAL
  10. GRB040825B, BVRcIc field photometry
  11. GRB040825A, BVRcIc field photometry
  12. GCN GRB OBSERBATION REPORT
  13. GRB 040825A,optical observations
  14. Increase of SGR 1806-20 activity
  15. GRB 040825A: Optical observations.
  16. GRB040825B: Correction to GCN 2657
  17. GRB 040825: Optical observations
  18. GRB 040812: Second epoch CXO Observations
  19. GRB040823,optical observation
  20. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  21. XRF 040812: optical observation at VLT
  22. GRB 040812: Optical counterparts of CXO sources
  23. XRF040812: possible afterglow
  24. CXO observation of GRB 040812
  25. IPN/HETE localizations of GRB040810 (=H3489)
  26. GRB 040812: Keck and LCO optical observations
  27. GRB 040812: Keck and LCO observations
  28. GRB 040812: radio observations
  29. GRB040812, optical/IR observations
  30. Konus-Wind observation of GRB040810 (=H3489)
  31. GRB 040812: a long GRB detected by INTEGRAL
  32. GRB 040810: Optical observations of a limited region
  33. IPN/HETE triangulation of GRB040802 (=H3485)
  34. GRB 040730, infrared observations
  35. GRB 040730: Optical observations
  36. GRB 040730: a long GRB detected with INTEGRAL
  37. Ongoing activity of SGR 1806-20
  38. GRB040624: optical monitoring at TNG
  39. Cancellation of IBAS/INTEGRAL GRB alerts
  40. IBAS Alert 1836: NOT a real GRB
  41. GRB040709 J,H-band observations
  42. GRB 040624: optical observations
  43. GRB 040624: optical observations at TNG and VLT
  44. MASTER: GRB 040624 optical observation after 0,48d
  45. GRB 040624: R-band observations
  46. GRB 040624, optical observations
  47. GRB 040624 - A long GRB detected with INTEGRAL
  48. GRB 030329: Rebrightening of hyperluminal ejecta.
  49. IPN Summary of SGR1806-20 Activity in 2004
  50. GRB040511: Retraction of redshift identification
  51. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  52. GRB 040606: Optical observations
  53. MASTER: HETE Alert 3274 optical observation
  54. Activivty of SGR 1806-20
  55. IPN triangulation of an intense intermediate burst from SGR1806-20
  56. GRB 040511, very fast decay?
  57. GRB 030324: Detection and Color of Host Galaxy
  58. GRB 040511: NIR observations with REM
  59. GRB040511: Redshift identifcation
  60. GRB 040511: Optical limit
  61. IBAS GRB Alerts n.1785 to 1791
  62. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  63. GRB 040511: Second Epoch Optical Observations
  64. IBAS GRB Alerts 1781-4
  65. GRB 040511: Optical observations
  66. GRB 040511: Optical Observations
  67. GRB040511: Optical Observations
  68. GRB040511: Optical Observations
  69. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  70. IBAS GRB Alert number 1774: NOT a real GRB
  71. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  72. IBAS Alerts 1771 and 1772: NOT a real GRB
  73. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  74. IPN triangulation of GRB040425 (=H3183)
  75. GRB040422: optical observations at CrAO
  76. GRB 040423 (=H3175): A Long GRB Localized by HETE
  77. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  78. GRB040422, BVRcIc field calibration
  79. GRB 040422,optical observation
  80. GRB 040422: a long GRB detected with INTEGRAL
  81. GRB 040403, deep optical observations
  82. INTEGRAL-SPI/ACS GRB data: timing correction
  83. IBAS GRB alerts 1739, 1740, 1741
  84. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  85. GRB 040403: Optical Observations
  86. GRB 040403 Optical Observations
  87. GRB 040403: Optical observations
  88. GRB 040403: optical observations
  89. GRB 040403: Optical Observations
  90. GRB 040403: a long GRB detected with INTEGRAL
  91. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  92. IBAS GRB Alert 1694
  93. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  94. GRB 040323, a dark GRB ?
  95. short hard GRB 040322
  96. GRB 040323: a long GRB detected with INTEGRAL
  97. IBAS GRB alerts 1679, 1680, 1681
  98. GRB040223: Deep NIR NTT data re-analysis
  99. GRB 040223: XMM-Newton results
  100. GRB040223, improved XMM position

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