We re-examined the angular dependence of the radiation from the intrinsic Josephson junctions in rectangular mesas of Bi$_2$Sr$_2$CaCu$_2$O$_{8+delta}$, in order to determine if the cavity mode part of the radiation arises from waves across the width
$w$ or along the length $ell$ of the mesas, associated with ``hot spots [Wang {it et al.}, Phys. Rev. Lett. {bf 105}, 057002 (2010)]. We derived analytic forms for the angular dependence expected in both cases for a general cavity mode in which the width of the mesa corresponds to an integer multiple of one-half the wavelength of the radiation. Assuming the coherent radiation from the $ac$ Josephson current source and the cavity magnetic surface current density source combine incoherently, fits to the data of Kadowaki {it et al.} [J. Phys. Soc. Jpn. {bf 79}, 023703 (2010)] on a mesa with mean $ell/w=5.17$ for both wave directions using two models for the incoherent combination were made, which correspond to standing and traveling waves, respectively. The results suggest that the combined output from the uniform $ac$ Josephson current source plus a cavity wave forming along the rectangle length is equally probable as that of the combined output from the uniform $ac$ Josephson current plus a cavity wave across the width. However, for mesas in which $nell/2w$ is integral, where $n$ is the index of the rectangular TM$^z_{n,0}$ mode, it is shown that standing cavity mode waves along the length of the mesa do not radiate in the $xz$ plane perpendicular to the length of the mesa, suggesting experiments on such mesas could help to resolve the question.
In superconducting ferromagnets for which the Curie temperature $T_{m}$ exceeds the superconducting transition temperature $T_{c}$, it was suggested that ferromagnetic spin fluctuations could lead to superconductivity with p-wave spin triplet Cooper
pairing. Using the Stoner model of itinerant ferromagnetism, we study the feedback effect of the p-wave superconductivity on the ferromagnetism. Below $T_{c}$, the ferromagnetism is enhanced by the p-wave superconductivity. At zero temperature, the critical Stoner value for itinerant ferromagnetism is reduced by the strength of the p-wave pairing potential, and the magnetization increases correspondingly. More important, our results suggest that once Stoner ferromagnetism is established, $T_m$ is unlikely to ever be below $T_c$. For strong and weak ferromagnetism, three and two peaks in the temperature dependence of the specific heat are respectively predicted, the upper peak in the latter case corresponding to a first-order transition.
