The Carnegie Supernova Project I

Optical spectroscopy of stripped-envelope supernovae

¹ Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
e-mail: max@phys.au.dk
² Carnegie Observatories, Las Campanas Observatory, Casilla 601, La Serena, Chile
³ Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101, USA
⁴ Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, B1900FWA, La Plata, Argentina
⁵ Instituto de Astrofísica de La Plata (IALP), CCT-CONICET-UNLP, Paseo del Bosque s/n, B1900FWA, La Plata, Argentina
⁶ Kavli Institute for the Physics and Mathematics of the Universe(WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583, Japan
⁷ Fundación Chilena de Astronomía, El Vergel 2252 #1501, Santiago, Chile
⁸ Hagler Institute for Advanced Studies, Texas A&M University, College Station, TX 77843, USA
⁹ DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, 2800 Kgs. Lyngby, Denmark
¹⁰ George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A&M University, College Station, TX 77843, USA
¹¹ European Southern Observatory, Alonso de Córdova 3107, Casilla 19, Santiago, Chile
¹² Institute for Astronomy, University of Hawai’i, 2680 Woodlawn Drive, Honolulu, HI 96822, USA
¹³ Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks, Rm 100, Norman, OK 73019, USA
¹⁴ Aix-Marseille Univ, CNRS, CNES, LAM, Marseille, France
¹⁵ Department of Physics, Florida State University, 77 Chieftain Way, Tallahassee, FL 32306, USA
¹⁶ Instituto de Astronomia y Ciencias Planetarias, Universidad de Atacama, Copayapu 485, Copiapo, Chile

Received: 20 February 2022
Accepted: 26 February 2023

Abstract

We present 170 optical spectra of 35 low-redshift stripped-envelope core-collapse supernovae observed by the Carnegie Supernova Project-I between 2004 and 2009. The data extend from as early as –19 days (d) prior to the epoch of B-band maximum to +322 d, with the vast majority obtained during the so-called photospheric phase covering the weeks around peak luminosity. In addition to histogram plots characterizing the redshift distribution, number of spectra per object, and the phase distribution of the sample, spectroscopic classification is also provided following standard criteria. The CSP-I spectra are electronically available and a detailed analysis of the data set is presented in a companion paper being the fifth and final paper of the series.