Novae and Supernovae
When a star accretes matter onto a white dwarf, the hydrogen will accumulate, and eventually detonate on the surface of the white dwarf. During this time, this "nova" may outshine 10,000 stars for a period of days or even weeks. However, when viewed in the light of hydrogen's Hα emission line, a nova will remain bright for months, or even years! Thus, Hα surveys are a great way to efficiently find large numbers of novae.
After each nova explosion, the process repeats. Eventually, the white dwarf mass should increase beyond 1.4 M☉, the Chandrasekhar limit. If this happens, the white dwarf will explode as a Type Ia supernovae.
Publications
Vinkó, J., Thomas, B.P., Wheeler, J.C., Ho, A.Y.Q., Mentuch Cooper, E., Gebhardt, K., Ciardullo, R., Farrow, D.J., Hill, G.J., Jäger, Z., Kollatschny, W., Liu, C., Regős, E., & Sárneczky, K. 2023, "Searching for Supernovae in HETDEX Data Release 3," Ap. J., 946, 31 [ADS Entry]
Darnley, M.J., Hounsell, R., O'Brien, T.J., Henze, M., Rodriguez-Gil, P., Shafter, A.W., Shara, M.M., Vaytet, N.M.H., Bode, M.F., Ciardullo, R., Davis, B.D., Galera-Rosillo, R., Harman, D.J., Harvey, E.J., Healy, M.W., Ness, J.-U., Ribeiro, V.A.R.M., & Williams, S.C. 2019, "A Recurrent Nova Super-Remnant in the Andromeda Galaxy," Nature, 565, 460 [ADS Entry]
Henze, M., Darnley, M.J., Williams, S.C., Kato, M., Hachisu, I., Anupama, G.C., Arai, A., Boyd, D., Burke, D., Ciardullo, R., Chinetti, K., Cook, L.M., Cook, M.J., Erdman, P., Gao, X., Harris, B., Hartmann, D.H., Hornoch, K., Horst, J.C., Hounsell, R., Husar, D., Itagaki, K., Kabashima, F., Kafka, S., Kaur, A., Kiyota, S., Kojiguchi, N., Kucakova, H., Kuramoto, K., Maehara, H., Mantero, A., Masci, F.J., Matsumoto, K., Naito, H., Ness, J.-U., Nishiyama, K., Oksanen, A., Osborne, J.P., Page, K.L., Paunzen, E., Pavana, M., Pickard, R., Prieto-Arranz, J., Rodríguez-Gil, P., Sala, G., Sano, Y., Shafter, A.W., Sugiura, Y., Tan, H., Tordai, T., Vrastil, J., Wagner, R.M., Watanabe, F., Williams, B.F., Bode, M.F., Bruno, A., Buchheim, B., Crawford, T., Goff, B., Hernanz, M., Igarashi, A.S., Jose, J., Motta, M., O'Brien, T.J., Oswalt, T., Poyner, G., Ribeiro, V.A.R.M., Sabo, R., Shara, M.M., Shears, J., Starkey, D., Starrfield, S., & Woodward, C.E. 2018, "Breaking the Habit: The Peculiar 2016 Eruption of the Unique Recurrent Nova M31N 2008-12a," Ap. J., 857, 68 [ADS Entry]
Shafter, A.W., Henze, M., Darnley, M.J., Ciardullo, R., Davis, B.D., Hawley, S.L. 2017, "The Recurrent Nova Candidate M31N 1966-08a = 1968-10c is a Galactic Flare Star," R.N.A.A., 1, 44 [ADS Entry]
Shafter, A.W., Darnley, M.J., Bode, M.F., & Ciardullo, R. 2012, "Spectroscopic Classes of Novae in M33," Ap. J., 752, 156 [ADS Entry]
Shafter, A.W., Darnley, M.J., Hornoch, K., Filippenko, A.V., Bode, M.F., Ciardullo, R., Misselt, K.A., Hounsell, R.A., Chornock, R., & Matheson, T. 2011, "A Spectroscopic and Photometric Survey of Novae in M31" Ap. J., 734, 12 [ADS Entry]
Brown, P.J., Roming, P.W.A., Milne, P., Bufano, F., Ciardullo, R., Elias-Rosa, N., Filippenko, A.V., Foley, R.J., Gehrels, N., Gronwall, C., Hicken, M., Holland, S.T., Hoversten, E.A., Immler, S., Kirshner, R.P., Li, W., Mazzali, P., Phillips, M.M., Pritchard, T., A1 Still, M., Turatto, M., & Vanden Berk, D. 2010, "The Absolute Magnitudes of Type Ia Supernovae in the Ultraviolet," Ap. J., 721, 1608 [ADS Entry]
Lai, S.-P., Chu, Y.-H., Chen, C.-H., Ciardullo, R., & Grebel, E.K 2001, "A Critical Examination of Hypernova Remnant Candidates in M101. I. MF 83," Ap. J., 547 754 [ADS Entry]
Wade, R.A., Harlow, J.J.B., & Ciardullo, R. 2000 "Biases in Expansion Distances of Novae Arising from the Prolate Geometry of Nova Shells" Pub. A.S.P. 112, 614 [ADS Entry]
Shafter, A.W., Ciardullo, R., & Pritchet, C. 2000, "Novae in External Galaxies: M51, M87, and M101," Ap. J., 530, 193 [ADS Entry]
Shafter, A.W., Ciardullo, R., & Pritchet, C.J. 1996, "Observations of Novae in M51, M87 and M101: A Preliminary Report," in I.A.U. Coll 158, Cataclysmic Variables and Related Objects, p. 291 [ADS Entry]
Schmidt, B.P., Suntzeff, N.B., Phillips, M.M., Schommer, R.A., Clocchiatti, A., Kirshner, R.P., Garnavich, P., Challis, P., Leibundgut, B., Spyromilio, J., Riess, A.G., Filippenko, A.V., Hamuy, M., Smith, R.C., Hogan, C., Stubbs, C., Diercks, A., Reiss, D., Gilliland, R., Tonry, J., Maza, J., Dressler, A., Walsh, J., & Ciardullo, R. 1998, "The High-z Supernova Search: Measuring Cosmic Deceleration and Global Curvature of the Universe Using Type IA Supernovae," Ap. J., 507, 46 [ADS Entry]
McMillan, R., & Ciardullo, R. 1996, "Constraining the Ages of Supernova Progenitors. I. Supernovae and Spiral Arms," Ap. J., 473, 707 [ADS Entry]
Leibundgut, B., Schommer, R., Phillips, M., Riess, A.,Schmidt, B., Spyromilio, J., Walsh, J., Suntzeff, N., Hamuy, M., Maza, J., Kirshner, R.P., Challis, P., Garnavich, P., Smith, R.C., Dressler, A., & Ciardullo, R. 1996, "Time Dilation in the Light Curve of the Distant Type IA Supernova SN 1995K," Ap. J. (Letters), 466, L21 [ADS Entry]
Wade, R.A., Ciardullo, R., Jacoby, G.H., & Sharp, N.A. 1991, "A Sharpened H-alpha + [N II] Image of the Nebula Surrounding Nova V1500 Cygni [1975]," A. J., 102, 1738 [ADS Entry]
Ciardullo, R., Tamblyn, P., & Phillips, A.C. 1990, "A Search for Novae in M31 Globular Clusters," Pub. A.S.P., 102, 1113 [ADS Entry]
Ciardullo, R., Shafter, A.W., Ford, H.C., Neill, J.D., Shara, M.M., & Tomaney, A.B. 1990, "The H-alpha Light Curves of Novae in M31," Ap. J., 356, 472 [ADS Entry]
Ciardullo, R., Tamblyn, P., Jacoby, G.H., Ford, H.C., & Williams, R.E. 1990, "The Nova Rate in the Elliptical Component of NGC 5128," A. J., 99, 1079 [ADS Entry]
Wade, R.A., Ciardullo, R., Deveny, J.B., Jacoby, G.H., & Schoening, W.E. 1990, "An Hα Image of Nova V1500 Cygni Twelve Years After Outburst," Lecture Notes on Physics, IAU Colloq. 122: Physics of Classical Novae, 369, 195 [ADS Entry]
Ford, H.C., & Ciardullo, R. 1988, "Novae as Distance Indicators", A.S.P. Conf. Ser. 4, The Extragalactic Distance Scale, (San Francisco: ASP), p. 128 [ADS Entry]
Ciardullo, R., Ford, H.C., Neill, J.D., Jacoby, G.H., & Shafter, A.W. 1987, "The Spatial Distribution and Population of Novae in M31," Ap. J., 318, 520 [ADS Entry]
Ciardullo, R., Ford, H., & Jacoby, G. 1983, "H-alpha Observations of Four Novae in M31," Ap. J., 272, 92 [ADS Entry]