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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"

43623 results found.

  1. GRB040912 (= H3557): Chandra Observations Scheduled
  2. GRB 040912: Optical Observations
  3. GRB/XRF040912,optical observations
  4. GRB 040912, BVRI observations
  5. An intense burst from SGR1806-20
  6. GRB040912 : Kiso Optical follow-up observation
  7. IBAS GRB Alerts 1978-1980
  8. Optical observations of field of GRB040912
  9. HETE 3557: Optical observations
  10. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  11. GRB 040827: XMM-Newton data
  12. GRB040903 - A XRF?
  13. GRB040827: analysis of the XMM-Newton observation
  14. GRB040903, REM near-IR observation
  15. GRB 040903 - INTEGRAL data analysis
  16. IBAS Alert 1974. Not a real GRB
  17. Very bright burst detected from SGR 1806-20
  18. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  19. Possible GRB 040903 detected with INTEGRAL
  20. GRB 040827 - Radio Observations
  21. XMM-Newton Images of GRB 040827
  22. GRB040825A: Optical observations
  23. GRB 040827: optical and NIR observations at the VLT
  24. GRB 040827: UKIRT - 2nd epoch K-band imaging
  25. GRB 040827: 2nd epoch of Magellan K-band imaging
  26. GRB 040827: K imaging - no evidence of variability
  27. GRB 040827: Detection of NIR afterglow
  28. GRB 040827: Possible detection of optical afterglow
  29. GRB040827 XMM-Newton observation
  30. GRB040825A: optical limit before GRB
  31. GRB 040825B: Optical observations
  32. GRB040827 optical observations
  33. GRB 040827 - Refined position
  34. GRB 040827 - A long GRB detected by INTEGRAL
  35. GRB040825B, BVRcIc field photometry
  36. GRB040825A, BVRcIc field photometry
  37. Increase of SGR 1806-20 activity
  38. GRB040825A: optical observations
  39. GRB040825B: optical observations
  40. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  41. GRB 040825A: Optical observations.
  42. GRB 040825: Optical observations
  43. XRF040812: possible afterglow second Chandra observation
  44. GRB 040812: Second epoch CXO Observations
  45. GRB040823,optical observation
  46. XRF040812: GMRT observations
  47. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  48. XRF 040812: optical observation at VLT
  49. GRB 040812: Optical counterparts of CXO sources
  50. XRF040812: possible afterglow
  51. CXO observation of GRB 040812
  52. Bursting activity from SGR 1806-20 detected with IBAS
  53. IPN/HETE localizations of GRB040810 (=H3489)
  54. GRB 040812: Keck and LCO optical observations
  55. GRB 040812: Keck and LCO observations
  56. GRB 040812: radio observations
  57. GRB040812, optical/IR observations
  58. Konus-Wind observation of GRB040810 (=H3489)
  59. GRB 040812: a long GRB detected by INTEGRAL
  60. GRB 040810: Optical observations of a limited region
  61. XRF040701: Optical Observations at ESO
  62. IPN/HETE triangulation of GRB040802 (=H3485)
  63. GRB 040730, infrared observations
  64. GRB 040730: Optical observations
  65. GRB 040730: a long GRB detected with INTEGRAL
  66. Ongoing activity of SGR 1806-20
  67. GRB040624: optical monitoring at TNG
  68. XRF 040701 - optical observations of the decaying Chandra source
  69. XRF040701: Second-Epoch Chandra Observations
  70. XRF040701: VLA Observations
  71. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  72. XRF040701: First-Epoch Chandra Observations
  73. IBAS Alert 1836: NOT a real GRB
  74. GRB040709 J,H-band observations
  75. GRB040624, optical observations
  76. XRF 040701, optical observations
  77. XRF040701 (=U11548): a bright XRF detected by HETE
  78. GRB 040624: optical observations
  79. Optical Observations of GRB040624
  80. GRB 040624: optical observations at TNG and VLT
  81. GRB 040624: R-band observations
  82. GRB 040624, optical observations
  83. GRB 040624 - A long GRB detected with INTEGRAL
  84. GRB 030329: Rebrightening of hyperluminal ejecta.
  85. IPN Summary of SGR1806-20 Activity in 2004
  86. GRB040511: Retraction of redshift identification
  87. SGR 1806-20: no IR variability of the proposed counterparts
  88. SGR 1806-20, potential NIR counterpart
  89. GRB 040606: Optical observations
  90. Activivty of SGR 1806-20
  91. IPN triangulation of an intense intermediate burst from SGR1806-20
  92. GRB 040511, very fast decay?
  93. GRB 030324: Detection and Color of Host Galaxy
  94. GRB 040511: NIR observations with REM
  95. GRB040511: Redshift identifcation
  96. GRB 040511: Optical limit
  97. GRB040511: Candidate optical/NIR afterglow
  98. IBAS GRB Alerts n.1785 to 1791
  99. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  100. GRB 040511: Second Epoch Optical Observations

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