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Early-time observations of Type Ia supernovae (SNe Ia) are essential to constrain their progenitor properties. In this paper, we present high-quality light curves of 127 SNe Ia discovered by the Zwicky Transient Facility (ZTF) in 2018. We describe our method to perform forced point spread function (PSF) photometry, which can be applied to other types of extragalactic transients. With a planned cadence of six observations per night ($3g+3r$), all of the 127 SNe Ia are detected in both $g$ and $r$ band more than 10,d (in the rest frame) prior to the epoch of $g$-band maximum light. The redshifts of these objects range from $z=0.0181$ to 0.165; the median redshift is 0.074. Among the 127 SNe, 50 are detected at least 14,d prior to maximum light (in the rest frame), with a subset of 9 objects being detected more than 17,d before $g$-band peak. This is the largest sample of young SNe Ia collected to date; it can be used to study the shape and color evolution of the rising light curves in unprecedented detail. We discuss six peculiar events in this sample, including one 02cx-like event ZTF18abclfee (SN,2018crl), one Ia-CSM SN ZTF18aaykjei (SN,2018cxk), and four objects with possible super-Chandrasekhar mass progenitors: ZTF18abhpgje (SN,2018eul), ZTF18abdpvnd (SN,2018dvf), ZTF18aawpcel (SN,2018cir) and ZTF18abddmrf (SN,2018dsx).
While it is clear that Type Ia supernovae (SNe) are the result of thermonuclear explosions in C/O white dwarfs (WDs), a great deal remains uncertain about the binary companion that facilitates the explosive disruption of the WD. Here, we present a co
In this first paper in a series we present 1298 low-redshift (zleq0.2) optical spectra of 582 Type Ia supernovae (SNe Ia) observed from 1989 through 2008 as part of the Berkeley SN Ia Program (BSNIP). 584 spectra of 199 SNe Ia have well-calibrated li
SN 2014J in M82 is the closest Type Ia supernova (SN Ia) in decades. The proximity allows for detailed studies of supernova physics and provides insights into the circumstellar and interstellar environment. In this work we analyze Spitzer mid-IR data
We present a photometric study of 17 Type Ia supernovae (SNe) based on multi-color (Bessell BVRI) data taken at Piszkesteto mountain station of Konkoly Observatory, Hungary between 2016 and 2018. We analyze the light curves (LCs) using the publicly a
We present early phase observations in optical and near-infrared wavelengths for the extremely luminous Type Ia supernova (SN Ia) 2009dc. The decline rate of the light curve is $Delta m_{15}(B)=0.65pm 0.03$, which is one of the slowest among SNe Ia.