To get accurate information additional information such as the specific lamp being used (make, voltage, current, and anything else possible) is needed. The maker should have that information out there if its to be used somewhere where photometrics need be considered.
That is good informatino for starting, but it doesn't make certain that such information can be acquired.
Photometrics unless on a lamp that has a reflector pre-mounted on it as a photometric system such as a PAR, R, or MR lamp is normally a fixturephotometrics question, and not a term associated with non-pre assembled reflector based lamps themselves. Photometrics Handbook has numorous fixtures using the same lamp but later a general section for instance when it comes to PAR 64 lamps as a photometric data class on it's own no matter the brand or type of fixture.
Are you installing the lamp itself into a fixture that has a perminant reflector, or is the reflector a part of the lamp/reflector assembly you are installing each time you change the lamp? Is the reflector coming with the lamp and often in a box like frame or just the lamp itself with the reflector that stays in place?
(Word of caution also in dealing with this type of lamp - just in case, read both the lamp manufacturer warnings and fixture warnings and practices for handeling such lamps. Explodes with the concussion of a grenade while hot is correct - and glass would not be fun to have picked out of your skin much less eyes.) Also, Osram has as part of the doccuments and further readings on this and their arc lamps a excellent PDF book on arc source lamp design, much less also articles to be found on care and handeling of xenon lamps. Other companies might also, while searching the net for alternatives if you are, spend time reading up on the lamp. Even if not using their lamp, such books/info even if coming from say Ushio's at one point less formal "Dr.Bulb" are a good read to understand any lamps under study better.
I'm not aware of any reflectorized xenon lamps that are larger than 300w. that have a reflector manufactured to be a one piece lamp/reflector, so photometrics of a 2Kw xenon lamp definately would not be a lamp question/term. Normally such 67mm, 82.5mm and 32.9mm reflector based xenon lamps at 100, 180 and 300w in having a reflector, which you than could compare photometric data on between brands would at most be rated fpr 300w and used on a very expensive video projector and would be doubtful to compare much given it's cost. Such lamps might also be liquid instead of gas filled which is a whole new ball park in lamp efficiency. Also if the case of why you are studying these lamps, think a 2Kw xenon lamp is expensive, wait until you get into projector or even Big Light lamps. This much less at one point on a 2Kw xenon lamp brand a certain lot number of them which were fine except 1/4" short in overall length shorter and for some reason unless that specific MOL were re-produced, the lamps would not work. Attach a 1/4" spacer to the lamp and it works fine, without it, the lamp don't work in the fixture. One lamp needs the heater/ignition wire, the other doesn't and works best without it. Yep in having two brands of fixture using the same wire there was some R&D on my part in tying a new ignition wire around the globe as to what gauge of wire would work best in not instantly burning up. Just as with the Martin Atomic 3000 lamp, yes it as a fixture is using a Osram XOP 15.OF lamp, but the Osram lamp comes without the ignition wire and won't work in the fixture. Someone at Martin is taking the Osram lamp and tying the heater wire about it or OEM'ing the lamp from Osram in being the only sub-manufacturer of it unless one has the time to tie a wire about the xenon 1,500w lamp. You can only get this lamp from Martin or from someone that's also buying it from Martin but perhaps has a larger discount/dealer factor with them than you do given Martin sells to the public. Only one supplier of this lamp unless other suppliers of the lamp in some way not also coming from Martin have time on their hands sufficient to artistically reproduce the heater wire applied to a base Osram lamp. Xenon lamps are both expensive and complex in details about them above even metal hallide lamps.
This photometric question is probably mis-termed in attempting to compare the lamp specifications of 2Kw xenon lamps in general to each other. All arc source lamps including these are compared by way of arc gap, wattage/voltage, CRI, Luminous output, Color Temperature and Lamp life as the comparison data about lamps all will have in common to compare in that specific lamp's specification. Believe also "bod rate" for arc source lamps though the term and usage could be incorrect. Some 2Kw lamps in a say follow spot produce a better and more steady/non-flickering beam of light than others. A movie projector in what lamp most of these lamps were designed for doesn't care in this bod/flicker factor as much as a followspot will in not seeming to flicker. Always in this class and price of lamp, get to be a good friend with your fixture supplier and ask their advice and recommendation on lamps - don't try to out guess a 2Kw xenon lamp using fixture supplier where it comes to lamps, they have tried all lamps in that wattage already and what they specify or recommend for use is for a good reason. Mostly "bod rate" if proper term above. Your lamp manufacturers will often be of one of two classes of supplier for you, wishing to make a sale in possibly something cheaper that will work, or someone that has studied the lamps and knows in an absolute sense a difference between them in spite of cost. Some good suppliers out there, others just out to make a buck or who while they can get a lamp might push you towards another they have a larger profit margin on. Again, consult the fixture manufacturer in choosing this type of lamp before purchasing any lamps from a supplier.
On the other hand, in not really knowing what specific lamp you are asking about, it could be a strobe or photo flash lamp also at that wattage such as with a Usho UA-96UV. This much less some form of 2Kw strobe lamp that could be out there.
On the most likely application in your question - a follow spot lamp, you for instance can install a XBO 2000w.HS.ofr in a Super Trooper II and a Lycian 1290 but the photometric data of two fixtures using the same lamp will be hopefully close but the answer will be that of the photometric data of the fixture not the lamp.
Next question is what specific lamps are you looking to compare, and in what specific fixtures? Keep in mind also that photometrically, the difference between say a 29 degree beam angle and a thirty degree beam angle will mis-lead one in comparision of fixtures one to one given different beam angles. To do a true photometric comparison of fixtures, one must do a bit of math when dissimilar beam angles or lens types are provided to figure out the same base of data for comparison.
I'm aware of 39 specific 2Kw Xenon lamps amongst three types of lamp base from Sfa 25-24 to Cable/Ceramic such as used in a 2Kw strobe lamp. Need to refine this specific lamp you are looking into a bit.
LTI, OSC, Christie, Ushio, ORC, Hanovia, Philips, Yumex, Osram, and G.E. are the major suppliers of xenon lamps. Eiko and Amglo possibly either are also or will soon also supply them in the theorized follow spot lamp. Amglo for instance was at one point the supplier of the #0439 Diversitronics 3000 strobe light lamp. They make xenon lamps also.
That's a supplier type of thing, what's recommended however would be to stick to what the manufacturer recommends for the fixture amongst brands. After that, brand to brand, cross comparing the specificications for this specific very expensive lamp is a good thing in cost effectiveness verses output/life. Not a cheap lamp, or in use one that is easy to become cost effective in using. There are alternatives and even in the case of a lamp that has a flicker rate that's a bit slow, at times one will never notice such a flickering by way of the follow spot.