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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"

32510 results found.

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

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