Heavy Meson Masses in Chiral Perturbation Theory with Heavy Quark Symmetry

The $SU(3)$ and hyperfine mass splittings of mesons containing a single heavy quark are computed to one-loop order in chiral perturbation theory with heavy quark spin symmetry. Electromagnetic contributions of order $\alpha_em$ are included. The observed values of the mass splittings are consistent with the one-loop chiral perturbation theory calculation. The $d-u$ hyperfine splitting $(D^{* +} - D^+) - (D^{*0} - D^0)$ is equal to $(m_d - m_u)/ m_s$ times the $s-d$ hyperfine splitting $(D_s^{* +} - D_s^+) - (D^{*+} - D^+)$ upto electromagnetic contributions. The small observed value of the $s-d$ hyperfine splitting implies that the $d-u$ hyperfine splitting is completely dominated by electromagnetic mass contributions.Comment: (28 pages, 2 figures included using uufiles, uses harvmac), CERN-TH.6765/9

Kaon Condensation in ``Nuclear Star" Matter

The critical density for kaon condensation in ``nuclear star" matter is computed up to two-loop order {\it in medium} (corresponding to next-to-next-to-leading order in chiral perturbation theory in free space) with a heavy-baryon effective chiral Lagrangian whose parameters are determined from $KN$ scattering and kaonic atom data. To the order considered, the kaon self-energy has highly non-linear density dependence in dense matter. We find that the four-Fermi interaction terms in the chiral Lagrangian play an important role in triggering condensation, predicting for ``natural" values of the four-Fermi interactions a rather low critical density, $\rho_c < 4 \rho_0$.Comment: 12 pages and 2 figures(LaTeX), SNUTP-94-28. The fig. 3 is replaced, with some changes in the text but the conclusion is not affected by these change

The Role of Lambda(1405) in Kaon-Proton Interactions

S-wave $K^-p$ scattering into various channels near threshold are analyzed in heavy-baryon chiral perturbation theory with $\Lambda (1405)$ introduced as an independent field. This is the approach that predicted the critical density $2<=\rho_c/\rho_0 <=3$ for negatively charged kaon condensation. We show that chiral perturbation expansion treating the $\Lambda (1405)$ as elementary is consistent with {\it all} threshold data including a double-charge-exchange process suppressed at leading order of chiral expansion in the absence of the $\Lambda (1405)$. We also discuss S-wave $K^+ p$ scattering phase shifts at low energy.Comment: 12 pages, epsfig.sty, 1 figure (uuencoded

Who Should Govern Congress? Access to Power and the Salary Grab of 1873

We examine the politics of the %u201CSalary Grab%u201D of 1873, legislation that increased congressional salaries retroactively by 50 percent. A group of New England and Midwestern elites opposed the Salary Grab, along with congressional franking and patronage-based civil service appointments, as part of reform effort to reshape %u201Cwho should govern Congress.%u201D Our analyses of congressional voting confirm the existence of this non-party elite coalition. While these elites lost many legislative battles in the short-run, their efforts kept reform on the legislative agenda throughout the late-nineteenth century and ultimately set the stage for the Progressive movement in the early-twentieth century.

Heavy Meson Hyperfine Splittings: A Puzzle for Heavy Quark Chiral Perturbation Theory

We show that there is a large discrepancy between the expected light flavor dependence of the heavy pseudoscalar--vector mass splittings and the measured values. We demonstrate that the one--loop calculation is unreliable. Moreover, agreement with experiment requires the leading dependence on SU(3) symmetry breaking to be nearly cancelled, so that the heavy quark mass dependence is unknown and the expected dependence on the light quark mass is not realized.Comment: 11 pages (LaTeX, 2 PS figures available upon request), MIT-CTP#216

Codling moth control

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