So the Swift data is all public. Different people request observations of different supernovae. Sometimes multiple people request data on the same supernova. Other people could have requested data on a particular supernova but it was already being observed. Some of us people spend a lot of time monitoring the observations and modifying the observing plans accordingly. Some of us were involved in getting template observations. Others might have just pulled the public data from the archive and published it. Sometimes there are multiple versions of the photometry independently done and published. With my SOUSA archive, the same data might be tabulated and used by different people. So proper credit is a tricky thing, so here are some of my thoughts.
I recommend citing any papers which originally presented
Swift data on that object and where the data actually comes from (making
clear whether you are using their photometry or your own reduction for
example). For the data available on my website, you should cite the
Swift Optical/Ultraviolet Supernova Archive (SOUSA) paper as the source
< http://adsabs.harvard.edu/abs/2014Ap%26SS.354...89B
>, and the data files usually indicate if there was a previous
publication. If you make extensive use of the UVOT data and/or want advice on
the analysis, it might be appropriate to involve me and add me as a
coauthor. If you are using your own reduction of the data, make sure to indicate the calibration you used (which should be the updated version of Breeveld et al. 2011) and whether they are Vega or AB magnitudes.
If using the SOUSA data, I suggest adding something like this to the observations section:
This supernova was also observed in the UV with the Ultra-Violet/Optical Telescope (UVOT; \citealp{Roming_etal_2005} on the Swift spacecraft \citep{Gehrels_etal_2004}. The UV photometry was obtained from the Swift Optical/Ultraviolet Supernova Archive\footnote{http://swift.gsfc.nasa.gov/docs/swift/sne/swift\_sn.html} (SOUSA; \citealp{Brown_etal_2014}). The reduction is based on that of \citet{Brown_etal_2009}, including subtraction of the host galaxy count rates and uses the
revised UV zeropoints and time-dependent sensitivity from \citet{Breeveld_etal_2011}.
and in the acknowledgements:
The work made use of Swift/UVOT data reduced by P. J. Brown and released in the Swift Optical/Ultraviolet Supernova Archive (SOUSA). SOUSA is supported by NASA's Astrophysics Data Analysis Program through grant NNX13AF35G.
