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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"

36154 results found.

  1. IPN triangulation of GRB030422C (annulus)
  2. IPN triangulation of GRB030422B (annulus)
  3. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  4. GRB030329: optical polarization
  5. IPN triangulation of GRB030422 (two large error boxes)
  6. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  7. IPN triangulation of GRB030421 (annulus)
  8. MASTER:optical observations GRB030418
  9. MASTER:optical observations probable GRB030414
  10. GRB030329: 444 AAVSO Measurements
  11. IPN triangulation of GRB030419 (annulus)
  12. MASTER:optical observations GRB030416
  13. ROTSE-III prompt optical detections of GRB 030418
  14. GRB030418: Upper limits from recent and historical observations.
  15. GRB030418: Kiso near infrared observations
  16. GRB 030418: Optical afterglow
  17. GRB 030418: Finder for afterglow candidate
  18. GRB 030418: Optical afterglow candidate
  19. GRB 030329 OT position
  20. OT GRB 030329: early UBVRcIc spectral evolution
  21. GRB030329, UBVRI polarimetry, R-polarization
  22. GRB 030329: SARA Optical Observations
  23. OT GRB 030329: early spectrum
  24. GRB030329: VR Photometry at TNG
  25. GRB030324: Candidate Optical Afterglow (Erratum)
  26. GRB030324: Candidate Optical Afterglow
  27. IPN triangulation of GRB030414 (small error box)
  28. GRB 030413: Optical Observations
  29. GRB 030329 Rc observations
  30. IPN triangulation of GRB030413 (small error box)
  31. IPN triangulation of GRB030410 (annulus)
  32. Superluminal motion in GRB 030329 (Correction)
  33. Superluminal motion in GRB 030329
  34. GRB 030329 and SN 2003dh
  35. GRB030329, optical position
  36. GRB 030329 VLBA Observations
  37. IPN triangulation of GRB030406 (small error box)
  38. IPN triangulation of GRB050403 (small error box)
  39. IPN triangulation of GRB030403 (annulus)
  40. GRB 030329: BVRI photometry at Asiago
  41. GRB 030329, light curve flattens
  42. GRB 030329: VLT V-band photometry
  43. If the SN/GRB connection confirmed
  44. GRB 030329: Supernova Confirmed
  45. GRB030329: RTT150 optical observations
  46. GRB030329: Near Infrared Observations at Gunma
  47. GRB030329: HET spectroscopic monitoring
  48. Kiso observation of the GRB030329 at April 6
  49. GRB 030329, color evolution
  50. GRB030328, UBVRcIc field photometry
  51. GRB 030329 Optical observations
  52. GRB 030329, color evolution
  53. GRB 030329: possible color change
  54. GRB030329: RTT150 optical observations
  55. GRB 030329: Supernova Spectrum Emerging
  56. GRB030329: Kiso B and R band observations
  57. GRB030329: RTT150 optical observation
  58. GRB030329: More AAVSO VR obs
  59. GRB030328: R upper limit after 6 hours by MASTER
  60. GRB 030329: BV photographic observations
  61. GRB 030329: SARA Optical Observations
  62. GRB 030329: SARA Optical Observations
  63. GRB030329, fading resumes
  64. GRB 030329, BVRI photometry
  65. SDSS 0.5m PT observations of GRB030329 (correction)
  66. SDSS 0.5m PT observations of GRB030329
  67. GRB 030329, Optical observations
  68. GRB 030329, nearby galaxies
  69. GRB030329, cessation of fading
  70. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  71. GRB 030329: Sub-millimeter detection
  72. GRB 030329: SARA Optical Observations
  73. GRB 030329: SARA Optical Observations
  74. OT GRB light curves and SN predictions
  75. GRB030329, optical observation
  76. GRB030329, new UBVRcIc field photometry
  77. GRB 030329, light curve and SN prediction
  78. GRB030329: optical observations at Tokyo Tech
  79. GRB 030329: optical observations
  80. GRB030329: multiple re-brightening phases
  81. GRB 030329, BRI photometry
  82. GRB 030329 , SPM optical observations
  83. GRB 030329: Radio observations at GMRT
  84. Further AAVSO V,B,R observations of GRB030329
  85. GRB 030329: Additional Mt. Laguna Optical Observations
  86. GRB 030329: SARA Optical Observations
  87. GRB 030329: Observations with ANDICAM
  88. GRB030329: further optical photometry and evidence for a light curve discontinuity
  89. GRB 030329: Correction to GCN 2056
  90. GRB 030329: fitting parameters and re-brightening
  91. GRB 030329: KAIT optical photometry
  92. GRB030329 Further RBO Optical Observations
  93. triangulation of GRB 030331 (single error box)
  94. GRB030329 - OT rebrightens
  95. GRB 030329: SARA Optical Observations
  96. AAVSO V & R observations of GRB030329
  97. IPN triangulation of GRB030331 (annulus)
  98. GRB 030329: optical observations
  99. IPN triangulation of GRB030329b (large error box)
  100. GRB 030329: beginning of the new fading phase in optical band

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