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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"

32509 results found.

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

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