The authors present measurements of the B {yields} {eta}K{gamma} branching fractions and upper limits for the B {yields} {eta}'K{gamma} branching fractions. For B{sup +} {yields} {eta}K{sup +}{gamma} they also measure the time-integrated charge asymmetry. The data sample, collected with the BABAR detector at the Stanford Linear Accelerator Center, represents 232 x 10{sup 6} produced B{bar B} pairs. The results for branching fractions and upper limits at 90% C.L. in units of 10{sup -6} are: {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = 11.3{sub -2.6}{sup +2.8} {+-} 0.6, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = 10.0 {+-} 1.3 {+-} 0.5, {Beta}(B{sup 0} {yields} {eta}'K{sup 0}{gamma})

We study the decays B 2![eta]{sub c}K and B° 2![eta]{sub c}K°, where the [eta]{sub c} is reconstructed in the K{sub S}° K{sup ±} [pi]{sup {-+}} and K+K− [pi]° decay modes. Results are based on a sample of 86 million B{bar B} pairs collected with the BABAR detector at the SLAC e+e− B Factory. We measure the branching fractions [Beta](B+ 2![eta]{sub c}K+) = (1.34 ± 0.09 ± 0.13 ± 0.41) x 10−3 and [Beta](B° 2![eta]{sub c}K°) = (1.18 ± 0.16 ± 0.13 ± 0.37) x 10−3, where the first error is statistical, the second is systematic, and the third reflects the [eta]{sub c} branching fraction uncertainty. In addition, we search for B 2![eta]{sub c}K events with [eta]{sub c} 2!2(K+K−) and [eta]{sub c} 2![phi][phi] and determine the [eta]{sub c} decay branching fraction ratios [Beta]([eta]{sub c} 2!2(K+K−))/[Beta]([eta]{sub c} 2!K{bar K}[pi]) = (2.3 ± 0.7 ± 0.6) x 10−2 and [Beta]([eta]{sub c} 2![phi][phi])/[Beta]([eta]{sub c} 2!K{bar K}[pi]) = (5.5 ± 1.4 {+-} 0.5) x 10−2.

We measure the branching fraction of the radiative B{sup -} decay {Beta}(B{sup -} {yields} {phi}K{sup -}{gamma}) = (3.46 {+-} 0.57{sub -0.37}{sup +0.39}) x 10{sup -6}, and set an upper limit on the radiative {bar B}{sup 0} decay {Beta}({bar B}{sup 0} {yields} {phi}{bar K}{sup 0}{gamma})

Observational evidence and theoretical motivation have led us to the conclusion that our current understanding of the universe is incomplete. While new physics is expected to exist above the electroweak scale, its influence can be detected by experiments that operate below this scale. The Babar experiment has recorded approximately 432 fb-1 of data at the center of mass energy of 10.58 GeV, which corresponds to the Y(4S) mass. One of the physics programs is studying radiative decays of the B meson. These decays primarily proceed through loop diagrams, and thus influences of new particles may be detectable. In this thesis, I present results of the measurements of the branching fractions, CP asymmetry, and isospin asymmetry of B -> K* gamma. Results are also presented for the measurements of the branching fractions of B -> rho(omega) gamma. Finally, a search for the decay of B -> phi gamma is given.

The authors present the results of searches for B decays to the two charmless two-body final states B° 2![eta]K*° and B 2![eta]K*, based on 20.7 fb−1 of data collected in 1999 and 2000 with the BABAR detector at PEP-II. They find the branching fractions [Beta](B° 2![eta]K*°) = (19.8 {sub -5.6}{sup +6.5} ± 1.7) x 10−6 and [Beta](B+ 2![eta]K*+) = (22.1 {sub -9.2}{sup +11.1} ± 3.3) x 10−6, where the first error quoted is the statistical and the second systematic.