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Dan MacIsaac, Gary Kanner, and Graydon Anderson. "Basic Physics of the Incandescent Lamp (Lightbulb). The Physics Teacher. Vol. 37 no. 10 (December 1999): 520-525:Vanadium 50 said:Halogens and ordinary incandescents operate at the same filament temperatures, around 3300K.
OSRAM Sylvania:It is extremely difficult to maintain an average temperature [of ordinary incandescents] higher than about 2900 K
The tungsten-halogen light is similar to conventional non-halogen incandescent light in that it employs a tungsten filament in a gas-filled, light-transmitting envelope and emits the same type of light. The major differences are that a trace of halogen vapor (e.g., iodine or bromine) is added to the inert fill gas, the gas pressure (7-8 ATM) and bulb temperature (250° C to 600° C) are much higher than in non-halogen lamps, and the bulb is made of fused quartz (silica, SiO2), high-silica glass or aluminosilicate “hard” glass to withstand the high operating pressures and temperatures. Lastly, there is a higher color temperature, 2800° K to 3400° K for standard halogen product.
http://www.sylvania.com/ConsumerProducts/AutomotiveLighting/Products/Halogen/HowHalogenWorks.htm