You're thinking that what I'm conveying here, might be a component of the photon's spin? I was under the understanding that the photon traveled in "packages" or bundled units of several photons?
I said it before but will try again: Typically when an electron transitions from an excited state to a available lower energy state in an isolated atom (i.e. not caused by collision with another atom) there is both a reduction in the energy and angular momentum of that atom. This angular moment and energy reduction is now in the photon to make both conserved.
s far as photon being "in a package" that is not best classical way to look at it. The photon IS a package, if you want to use that term, but you can not "open the package" to see it. Typically the energy of the photon extends of 10s of centimeters along the direction of its travel and I don't know much about how widely it is distributed transverse to the direction of travel, but tend to think that in some classical sense is a few mm at most, probably less than one if the concept even makes any sense, which I doubt.
The length of the photon is inversely related to the transition probability of the electronic transition than made it. I.e. an isolated atom, which does not have the radiative process disturbed by a collision, will produce longer photons if the transition probably is low. These "long photons" will again in a classical sense, have more cycles of oscillation and thus have more precisely defined energy as it is proportional to their oscillation frequency. I.e. these spectral lines (many photons) will be sharp.
This is all related to the uncertanity principle of quantum mechanics. I.e. a precisely defined frequency is a small "delta E" so the "Delta T" will be large - I.e. it is less possible to tell when it was radiated or where it is when traveling - this is not-measurement difficulty, but a fundamental impossibility to know when it was emitted or where it is very precisely at any time - This shows up when you try to measure its length as it measures as "long."
It is not easy (perhaps impossible?) to make very long photons in the lab because the gasous source they would come from must have very low density to avoid collisions disturbing the longer lasting radiative process. That very low density source would need to be thousands of cubic meters in volume to give readily detected intensity (there are always noise sources in the detector) But some of lines from the Northern lines are very long - seveal meters. Especially the so called "Oxygen green line," which has very low transition probability as it is actually a first order forbidden transition.
