# TESS Program G04028

Title: Searching For Shock Signatures And Modeling Pulsation Hydrodynamics Of Galactic Cepheids

PI: Guzik, Joyce - New Mexico Consortium & Los Alamos National Laboratory

Type: SMALL

Summary: We propose observations of 46 bright Galactic Cepheids during TESS Cycle 4, with 2-min cadence desired. Our objective is to search for transient, possibly phased, brightenings in the optical light curves, indicative of pulsation-produced shocks. Hydrodynamic modeling has shown that shocks can plausibly explain X-ray brightenings discovered in delta Cep (phased) and beta Dor using Chandra and XMM observations. Shocks have been proposed to drive mass loss in Cepheids that may help explain the Cepheid mass discrepancy. Our second objective is to carry out nonlinear hydrodynamic modeling using MESA RSP for an ensemble of Galactic Cepheids to understand the origin of cycle-to-cycle period and amplitude variations, bumps, and other features that are being discovered in TESS Cepheid light curves.


# Sector 040 targets observed (2 min: 4, 20 s: 0)
403786081,288.9979,27.9263,5.58,G04171;G04028
311218292,284.5614,17.3609,4.58,G04028
375534411,294.1572,20.3329,5.75,G04028
303256075,37.9672,89.2641,1.37,G04134;G04028

# Sector 041 targets observed (2 min: 13, 20 s: 0)
100406081,310.8507,35.5878,6.43,G04028
106222137,301.1107,34.1122,7.76,G04028
42362686,302.2823,37.1519,8.85,G04028
92645571,303.0951,32.8716,8.14,G04028
285448217,296.2031,29.2647,6.33,G04028
403786081,288.9979,27.9263,5.58,G04171;G04028
11145790,297.8788,27.4602,5.92,G04028
282421297,299.3692,26.5564,8.32,G04028
375534411,294.1572,20.3329,5.75,G04028
435554567,297.0992,27.2865,6.95,G04028
368040266,312.8677,28.2505,4.78,G04034;G04028;G04125
188312699,308.2262,46.6012,8.06,G04028
272943843,297.0644,43.1269,8.32,G04028

# Sector 043 targets observed (2 min: 9, 20 s: 0)
118592633,69.3115,18.543,5.67,G04028
247585034,86.2632,13.5763,8.81,G04028
29455183,86.4189,18.6569,7.38,G04028
307375161,98.7394,15.3305,6.06,G04028;G04234
385904228,95.555,14.6781,7.52,G04028
456997268,100.7813,20.9391,9.16,G04028
171855358,97.142,30.493,8.06,G04028
400100492,90.1188,35.3122,7.04,G04028
81059100,91.6456,26.3292,8.73,G04028

# Sector 044 targets observed (2 min: 10, 20 s: 0)
247585034,86.2632,13.5763,8.81,G04028
29455183,86.4189,18.6569,7.38,G04028
118592633,69.3115,18.543,5.67,G04028
171855358,97.142,30.493,8.06,G04028
400100492,90.1188,35.3122,7.04,G04028
81059100,91.6456,26.3292,8.73,G04028
307375161,98.7394,15.3305,6.06,G04028;G04234
385904228,95.555,14.6781,7.52,G04028
456997268,100.7813,20.9391,9.16,G04028
436949033,106.0272,20.5703,3.62,G04028;G04125