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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"

45463 results found.

  1. GRB 031220 : Kyoto Optical Observation
  2. GRB 031220: Subaru observation
  3. GRB 031220: Optical observation at Tokyo Tech
  4. GRB031220: ROTSE-IIIb Optical Limits
  5. GRB031220 : Optical Observation of Lulin Observatory
  6. GRB 031203 I-band monitoring
  7. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  8. GRB 2974 follow-up observations
  9. GRB031203, improved XMM position
  10. GRB 031203: Discovery of a dust echo
  11. GRB031214 triangulation (annulus), [repost of GCN2487, subject corrected]
  12. GRB030921 triangulation (annulus)
  13. GRB 031203: SMARTS optical monitoring
  14. GRB 021203: A Normal GRB viewed far off axis?
  15. XMM-Newton Observations of GRB031203: Preliminary Images
  16. GRB 031203: Variable Radio Source
  17. GRB 031203: Magellan spectrum of possible GRB host
  18. GRB 031203: Optical/IR Astrometry
  19. IPN/HETE localization of GRB031203B (=H2949; large error box)
  20. GRB031203 K prime photometry: correction to galaxy coordinates
  21. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  22. XMM-Newton Observation of GRB031203
  23. GRB 031203: Deep NIR NTT & VLT observations
  24. GRB031203: K' Photometry of the likely GRB host
  25. XMM-Newton Observation of GRB031203
  26. GRB 031203: Radio detection
  27. GRB 031203: Further reports on December 4 observations
  28. GRB 031203: IR NTTobservations do not confirm REM detection
  29. GRB031203 : Optical Observation of Lulin Observatory
  30. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  31. GRB 031203: Apparent Spectral Break
  32. GRB031203: Planned XMM-Newton observation II
  33. GRB 031203: IR REM Observations
  34. GRB031203: Optical Observations
  35. GRB 031203 XMM-Newton observation
  36. GRB 031203: Optical/IR SMARTS Observations
  37. GRB031203: Planned XMM-Newton observation
  38. IPN triangulation of GRB031127A and B (quasi-simultaneous; large error boxes)
  39. GRB 031203: further analysis of INTEGRAL data
  40. GRB 031203: A long GRB detected with INTEGRAL
  41. IPN triangulation of GRB031201 (large error box)
  42. IPN triangulation of GRB031130 (large error box)
  43. GRB031111A, prompt optical observations
  44. GRB 030329: Planned XMM-Newton Observation
  45. IPN triangulation of GRB031120 (two large error boxes)
  46. GRB 031111B (= H2925) : Kyoto Optical Observation
  47. IPN/HETE localization of GRB031109 (=H2917; large error box)
  48. IPN detection of activity from SGR1806-20
  49. GRB 031111, Radio observations
  50. IPN triangulation of GRB031114 (large error box)
  51. IPN triangulation of GRB031107 (two large error boxes)
  52. GRB 031111: Optical observations
  53. GRB 031111, optical observations
  54. SN 2003jd (SN/GRB?) -- X-ray Observations
  55. HETE Prompt GRB Spectral Analyses
  56. IPN triangulation of GRB031111 (=H2924): small error box
  57. XRF031109 (=H2919): A very long XRF localized by HETE
  58. IPN triangulation of GRB031108 (large error box)
  59. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  60. GRB030929/SN2003jd association unlikely based on IPN localiztion
  61. IPN triangulation of GRB031027 (small error box)
  62. IPN triangulation of GRB031026B (large error box)
  63. Lulin optical follow-up observations of GRB031026
  64. SN 2003jd (SN/GRB?), Radio Observations
  65. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  66. GRB 031026: Further Ic Observations
  67. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  68. Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
  69. IPN triangulation of GRB031024 (single error box)
  70. GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
  71. GRB 031026: Ic Observations
  72. GRB031026 : KISO optical follow-up observation
  73. IPN triangulation of GRB031024 (annulus)
  74. IPN triangulation of GRB031020 (large error box)
  75. GRB030329: radio observations at RT-22 (CrAO)
  76. IPN triangulation of GRB031016 (two large error boxes)
  77. IBAS alert 1180 refers to a burst from SGR 1806-20
  78. HETE Prompt GRB Light Curves and Color-Color Diagrams
  79. IPN triangulation of GRB031014 (annulus)
  80. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  81. XRF 030824: additional observations at CFHT
  82. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  83. IPN triangulation of GRB031008 (annulus)
  84. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  85. IPN detection of continued activity from SGR1806-20
  86. IPN triangulation of GRB031007 (two large error boxes)
  87. XRF 030723: Subaru Optical Observations
  88. IPN triangulation of GRB031004B (annulus)
  89. IPN triangulation of GRB031004A (short/hard; annulus)
  90. IPN triangulation of GRB030929 (short/hard; annulus)
  91. A burst from SGR 1806-20 detected with IBAS
  92. XRF 030824: Early follow-up observation at Kiso observatory
  93. XRF 030824: observations at CFHT
  94. IPN triangulation of GRB030926 (short/hard; large error box)
  95. IPN triangulation of GRB030922B (large error box)
  96. XRF 030723: Detection of the likely host galaxy
  97. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  98. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  99. IPN triangulation of GRB030922A (large error box)
  100. IPN triangulation of GRB030921 (large error box)

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