• Mickael R, Mat S, Young-Lo K, Martin B (Lyon), Joel J, Ariel G, Suhail D, Mattia B, Ana S-C(Stockholm), Kate M, Jacco T, Luke H, Maxime D, Mark M (Trinity), Melissa A, Philippe R, Manu G (Cleremont), Bastien C, Benjamin R(Marseille), Nicolas R (Paris)

• ZTF21aaomuka: young and discovered by POISE (CSP group) @ z=0.07.
• ZTF21aamnngb: strong early time Calcium. Going in to the LT queue. z=0.016.
• RCF are going to automate classifications to TNS. Using SNIa score: aka Ia/non-Ia.

• Using the 2018 cosmology sample: objects with early and peak spectra: 50. 8 objects after S/N and coverage cuts cuts.
• TARDIS is a 1D spectral synthesis code.
• ZTF18abfhryc is the current focus: have fits to both spectra, and is trying to reconcile the two profiles.
  • Velocity profile moves from 30,000 km/s at early times to 20,000 km/s around peak.
• Lots to come from this project!

• Trying to predict the sensor contribution to the PSF.
• Using the methodology of Medford, Goldstein, Nugent+ used to deduce fringing.
• Tried to use the fringe pattern to estimate thickness profile: failed!
• New idea: silicon absorption varies as a function of wavelength => use flat fields to estimate thickness.
  • The ratio of two flat fields (at different wavelengths) should match the thickness profile.
  • Implemented a forward modelling approach with physics! Test against fringe maps.
  • Have to think about higher order issues: reflection within the camera. Use filterless flat field.
  • Use sky spectrum (over assuming a flat spectrum). This is old and needs to be improved.
  • Overall the fit is good, but there are issues: it's not great on small scales.
• It works!

• Two upcoming deadlines:
  • ESO (1st Oct - 31st March): deadline is 25th March
  • Gemini (1st Aug - 31st Jan): deadline is 31st March
• Plans within the group:
  • Lensing: MUSE+HAWKI (as currently; lead by Ariel); INT (to weed out contaminents; Suhail)
  • Early-time: X-SHOOTER (2-3 triggers; lead by Mattia B)
  • Gemini LLP (all transient classes, but esp. long lived events; lead by Adam M)
  • Local: HST (2-3 events to get TRGB of ZTF; Proof of Concept; organised by Suhail)
  • Hosts: MUSE (neary events ~10; pulled together by Mat).

ZTF Ia Phone-con: 2021-Mar-10

Meeting Agenda:

1. SNe of the week [Joel J]

2. TARDIS Modelling of early SNIa Spectra [Luke]

3. Measuring the thickness of the ZTF CCD [Philippe]

4. Proposal planning [Mat]

5. AOB / Close

Participants ():

• Mickael R, Mat S, Jeremy L, Martin B (Lyon), Joel J, Ariel G, Suhail D, Mattia B, Ana S-C (Stockholm), Jakob N, Valery B, Simeon R (Berlin), Kate M, Jacco T (Trinity), Melissa A, Philippe R (Cleremont), Benjamin R, Bastien C, Julian B (Marseille)

Notes:

Transients of the Week:

Luke on early time spectral modelling:

Philippe on CCD thickness:

Mat on Proposals:

Closing Remarks:

• Sign up for a talk!