A Linear Relation between the Color Stretch s <sub> BV </sub> and the Rising Color Slope s<sub>0</sub>*(B-V) of Type Ia Supernovae

Chen, Ping; Dong, Subo; Ashall, Chris; Benetti, S.; Bersier, D.; Bose, S.; Brimacombe, Joseph; Brink, Thomas G.; Buckley, David A. H.; Cappellaro, Enrico; Christie, Grant W.; Elias-Rosa, N.; Filippenko, Alexei V.; Gromadzki, Mariusz; Holoien, Thomas W. -S.; Hu, Shaoming; Kochanek, C. S.; Koff, Robert; Kollmeier, Juna A.; Lundqvist, P.; Mattila, S.; Milne, Peter A.; Munoz, J. A.; Mutel, Robert; Natusch, Tim; Nicolas, Joel; Pastorello, A.; Prentice, Simon; Prieto, J. L.; Roth, Tyler; Shappee, B. J.; Stone, Geoffrey; Stanek, K. Z.; Stritzinger, M. D.; Thompson, Todd A.; Tomasella, Lina; Villanueva, Steven
2023
ASTROPHYSICAL JOURNAL
DOI
10.3847/1538-4357/acc404
Using data from the Complete Nearby (redshift z (host) < 0.02) sample of Type Ia Supernovae (CNIa0.02), we find a linear relation between two parameters derived from the B - V color curves of Type Ia supernovae: the color stretch s ( BV ) and the rising color slope s(0)*(B-V) BV . The s ( BV ) parameter is known to be tightly correlated with the peak luminosity, especially for fast decliners (dim Type Ia supernovae), and the luminosity correlation with s ( BV ) is markedly better than with the classic light-curve width parameters such as ?m (15)(B). Thus, our new linear relation can be used to infer peak luminosity from s(0)* s ( BV ) (or ?m (15)(B)), the measurement of s(0)*(B-V)