GRB 170406***A***: Swift-BAT refined analysis S. D. Barthelmy (GSFC), J. R. Cummings (CPI), N. Gehrels (GSFC), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 170406***A*** (trigger #745966) (NAME, et al., GCN Circ. xxxx). The BAT ground-calculated position is RA, Dec = 282.082, -2.445 deg which is RA(J2000) = 18h 48m 19.8s Dec(J2000) = -02d 26' 40.4" with an uncertainty of 3.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. [Description about the mask-weighted light curve] T90 (15-350 keV) is 595.87 +- 452.83 sec (estimated error including systematics). The time-averaged spectrum from TTBD to TTBD sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.18 +- 1.18, and Epeak of 32.3 +- 5.3 keV (chi squared 43.42 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 2.5 +- 0.3 x 10^-06 erg/cm2 and the 1-sec peak flux measured from T+861.88 sec in the 15-150 keV band is 0.4 +- 0.1 ph/cm2/sec. A fit to a simple power law gives a photon index of 2.23 +- 0.18 (chi squared 56.56 for 57 d.o.f.). All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/745966/BA/