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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').
Advanced Search

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"

35981 results found.

  1. GRB040916: Archival optical observations
  2. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  3. GRB040916: Optical observations
  4. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  5. GRB040912 (= H3557): Chandra Observations Scheduled
  6. GRB 040912: Optical Observations
  7. GRB/XRF040912,optical observations
  8. GRB 040912, BVRI observations
  9. Optical observations of GRB/XRF 040912 = HETE 3557
  10. An intense burst from SGR1806-20
  11. IBAS GRB Alerts 1978-1980
  12. Optical observations of field of GRB040912
  13. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  14. GRB 040827: XMM-Newton data
  15. GRB040903 - A XRF?
  16. GRB040827: analysis of the XMM-Newton observation
  17. GRB 040903 - INTEGRAL data analysis
  18. IBAS Alert 1974. Not a real GRB
  19. Very bright burst detected from SGR 1806-20
  20. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  21. Possible GRB 040903 - further analysis
  22. Possible GRB 040903 detected with INTEGRAL
  23. GRB 040827 - Radio Observations
  24. XMM-Newton Images of GRB 040827
  25. GRB 040827: optical and NIR observations at the VLT
  26. GRB 040827: UKIRT - 2nd epoch K-band imaging
  27. GRB 040827: 2nd epoch of Magellan K-band imaging
  28. GRB 040827: K imaging - no evidence of variability
  29. GRB 040827: Detection of NIR afterglow
  30. GRB 040827: Possible detection of optical afterglow
  31. GRB 040827: RTT150 optical observations
  32. GRB040825A: optical limit before GRB
  33. GRB 040825B: Optical observations
  34. GRB040827 optical observations
  35. GRB 040827 : Planned XMM-Newton observation
  36. GRB 040827 - Refined position
  37. GRB 040827 : peak flux
  38. GRB 040827 - A long GRB detected by INTEGRAL
  39. GRB040825B, BVRcIc field photometry
  40. GRB040825A, BVRcIc field photometry
  41. GCN GRB OBSERBATION REPORT
  42. GRB 040825A,optical observations
  43. Increase of SGR 1806-20 activity
  44. GRB 040825A: Optical observations.
  45. GRB040825B: Correction to GCN 2657
  46. GRB 040825: Optical observations
  47. GRB 040812: Second epoch CXO Observations
  48. GRB040823,optical observation
  49. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  50. XRF 040812: optical observation at VLT
  51. GRB 040812: Optical counterparts of CXO sources
  52. XRF040812: possible afterglow
  53. CXO observation of GRB 040812
  54. IPN/HETE localizations of GRB040810 (=H3489)
  55. GRB 040812: Keck and LCO optical observations
  56. GRB 040812: Keck and LCO observations
  57. GRB 040812: radio observations
  58. GRB040812, optical/IR observations
  59. Konus-Wind observation of GRB040810 (=H3489)
  60. GRB 040812: a long GRB detected by INTEGRAL
  61. GRB 040810: Optical observations of a limited region
  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. Cancellation of IBAS/INTEGRAL GRB alerts
  69. IBAS Alert 1836: NOT a real GRB
  70. GRB040709 J,H-band observations
  71. GRB 040624: optical observations
  72. GRB 040624: optical observations at TNG and VLT
  73. MASTER: GRB 040624 optical observation after 0,48d
  74. GRB 040624: R-band observations
  75. GRB 040624, optical observations
  76. GRB 040624 - A long GRB detected with INTEGRAL
  77. GRB 030329: Rebrightening of hyperluminal ejecta.
  78. IPN Summary of SGR1806-20 Activity in 2004
  79. GRB040511: Retraction of redshift identification
  80. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  81. GRB 040606: Optical observations
  82. MASTER: HETE Alert 3274 optical observation
  83. Activivty of SGR 1806-20
  84. IPN triangulation of an intense intermediate burst from SGR1806-20
  85. GRB 040511, very fast decay?
  86. GRB 030324: Detection and Color of Host Galaxy
  87. GRB 040511: NIR observations with REM
  88. GRB040511: Redshift identifcation
  89. GRB 040511: Optical limit
  90. IBAS GRB Alerts n.1785 to 1791
  91. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  92. GRB 040511: Second Epoch Optical Observations
  93. IBAS GRB Alerts 1781-4
  94. GRB 040511: Optical observations
  95. GRB 040511: Optical Observations
  96. GRB040511: Optical Observations
  97. GRB040511: Optical Observations
  98. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  99. IBAS GRB Alert number 1774: NOT a real GRB
  100. Type Ic SN2001em (off-axis GRB jet?), optical spectrum

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