1. Niharika Sravan Midwest Relativity Meeting October 27, 2013 IMPORTANCE OF TIDES FOR PERIASTRON PRECESSION IN ECCENTRIC NEUTRON STAR - WHITE DWARF BINARIES

2. ONCE UPON A TIME…

3. AND THEN CAME THE GW OBSERVER

4. PERIASTRON PRECESSION Is driven by a combination of tidal, rotational and general relativistic effects Companion Star/Satellite The quadrupolar periastron precession constant k 2 is a measure of the WD's central concentration

5. ECCENTRIC NEUTRON STAR - WHITE DWARF BINARIES Seen in the field as pulsars orbiting WDs Serve as probes into compact object physics that are: Clean Testable Abundant

6. IMPORTANCE OF TIDES AND ROTATION IN J1141-6545 Is GR enough to place correct constraints on the WD mass?

8. TIDES DOMINATE IN 380 MYR Rotation GR Tides Total

9. GALACTIC NS-WD BINARIES

10. 0.5 Gyr 13.8 Gyr

11. OUR METHOD How bad can NOT accounting for tides be?

12. 0.5 Gyr 13.8 Gyr

13. “Alright, alright!! I get it, tides are important. But how do you expect me to accurately interpret periastron precession rate if I know nothing about the internal structure of the WD?”

14. ONCE AGAIN

15. FACILITATING MASS EXTRACTION: K 2 R WD 5 VS. M WD Use it well.

16. CONCLUSIONS Information about periastron precession rates can be used to place constraints on the properties of compact object binaries Tides can be a significant driver of periastron precession There is a simple relation that connects the WD structure parameters, governing periastron precession, to the WD mass

17. QUESTIONS?