We compute photoionization models for the giant extragalactic H II region NGC 5461 and compare their predictions to several observational constraints. Since we aim to reproduce not only the global properties of the region but also its local structure, the models are constrained to reproduce the observed density profile, and our analysis takes into

HH 444 is a stellar jet which is immersed in the H II region photoionized by sigma Orionis. Spatially resolved, high spectral resolution observations of the Hα and [N II] lambda lambda 6548, 6584 lines have been obtained for this object. These observations reveal for the first time the detailed velocity structure of the stellar jet and its

We have measured the periods and light curves of 148 RR Lyrae variables from V=13.5 to 19.7 from the first 100 deg2 of the Quasar Equatorial Survey Team RR Lyrae survey. Approximately 55% of these stars belong to the clump of stars detected earlier by the Sloan Digital Sky Survey. According to our measurements, this feature has ~10 times the

Data of the 1996 outburst of the single-known accreting millisecond pulsar SAX J1808.4-3658, taken with the Wide Field Cameras (WFCs) on BeppoSAX, are revisited with more complete data coverage and more comprehensive analysis techniques than in a previous report. An additional type-I X-ray burst was identified which occurred at a time when the

The TESLA Technical Design Report Part III: Physics at an e+e- Linear Collider

The time evolution equations of a simplified isolated ideal gas, the ``tetrahedral'' gas, are derived. The dynamical behavior of the López-Ruiz-Mancini-Calbet complexity [R. López-Ruiz, H. L. Mancini, and X. Calbet, Phys. Lett. A 209, 321 (1995)] is studied in this system. In general, it is shown that the complexity remains within the bounds of