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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"

45440 results found.

  1. GRB 040827: RTT150 optical observations
  2. GRB040827 XMM-Newton observation
  3. GRB040825A: optical limit before GRB
  4. MASTER: GRB040827 possible OT
  5. GRB 040825B: Optical observations
  6. GRB040827 optical observations
  7. GRB 040827 : Planned XMM-Newton observation
  8. GRB 040827 - Refined position
  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. GRB040825A: optical observations
  16. GRB040825B: optical observations
  17. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  18. GRB 040825A: Optical observations.
  19. MASTER: GRB040825a optical observation
  20. MASTER: GRB040825b optical observation
  21. GRB040825B: Correction to GCN 2657
  22. GRB 040825: Optical observations
  23. XRF040812: possible afterglow second Chandra observation
  24. GRB 040812: Second epoch CXO Observations
  25. GRB040823,optical observation
  26. XRF040812: GMRT observations
  27. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  28. XRF 040812: optical observation at VLT
  29. GRB 040812: Optical counterparts of CXO sources
  30. XRF040812: possible afterglow
  31. CXO observation of GRB 040812
  32. Bursting activity from SGR 1806-20 detected with IBAS
  33. IPN/HETE localizations of GRB040810 (=H3489)
  34. GRB 040812: Keck and LCO optical observations
  35. GRB 040812: Keck and LCO observations
  36. GRB 040812: radio observations
  37. GRB040812, optical/IR observations
  38. Konus-Wind observation of GRB040810 (=H3489)
  39. GRB 040812: a long GRB detected by INTEGRAL
  40. GRB 040810: Optical observations of a limited region
  41. XRF040701: Optical Observations at ESO
  42. IPN/HETE triangulation of GRB040802 (=H3485)
  43. GRB 040730, infrared observations
  44. GRB 040730: Optical observations
  45. GRB 040730: a long GRB detected with INTEGRAL
  46. Ongoing activity of SGR 1806-20
  47. GRB040624: optical monitoring at TNG
  48. XRF 040701 - optical observations of the decaying Chandra source
  49. XRF040701: Second-Epoch Chandra Observations
  50. Cancellation of IBAS/INTEGRAL GRB alerts
  51. XRF040701: VLA Observations
  52. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  53. XRF040701: First-Epoch Chandra Observations
  54. IBAS Alert 1836: NOT a real GRB
  55. GRB040709 J,H-band observations
  56. GRB040624, optical observations
  57. GRB040706:observation at University of Miyazaki
  58. XRF 040701, optical observations
  59. XRF040701 (=U11548): a bright XRF detected by HETE
  60. GRB 040624: optical observations
  61. Optical Observations of GRB040624
  62. GRB 040624: optical observations at TNG and VLT
  63. MASTER: GRB 040624 optical observation after 0,48d
  64. GRB 040624: R-band observations
  65. GRB 040624, optical observations
  66. GRB 040624 - A long GRB detected with INTEGRAL
  67. GRB 030329: Rebrightening of hyperluminal ejecta.
  68. IPN Summary of SGR1806-20 Activity in 2004
  69. GRB040511: Retraction of redshift identification
  70. SGR 1806-20: no IR variability of the proposed counterparts
  71. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  72. SGR 1806-20, potential NIR counterpart
  73. GRB 040606: Optical observations
  74. MASTER: HETE Alert 3274 optical observation
  75. Activivty of SGR 1806-20
  76. IPN triangulation of an intense intermediate burst from SGR1806-20
  77. GRB 040511, very fast decay?
  78. GRB 030324: Detection and Color of Host Galaxy
  79. GRB 040511: NIR observations with REM
  80. GRB040511: Redshift identifcation
  81. GRB 040511: Optical limit
  82. GRB040511: Candidate optical/NIR afterglow
  83. IBAS GRB Alerts n.1785 to 1791
  84. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  85. GRB 040511: Second Epoch Optical Observations
  86. GRB 040511: Optical observations
  87. GRB 040511: Optical Observations
  88. GRB040511: Optical Observations
  89. GRB040511: Optical Observations
  90. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  91. IBAS GRB Alert number 1774: NOT a real GRB
  92. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  93. IBAS Alerts 1771 and 1772: NOT a real GRB
  94. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  95. IPN triangulation of GRB040425 (=H3183)
  96. On Line Availability of Archival HETE Fregate Data and Lightcurves
  97. GRB040422: optical observations at Xinglong Observatory
  98. GRB040422: optical observations at CrAO
  99. GRB 040423 (=H3175): A Long GRB Localized by HETE
  100. GRB040422, optical observations at Loiano

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